Science.gov

Sample records for soil reference materials

  1. Multi-Elemental Nuclear Analysis of soil reference material

    NASA Astrophysics Data System (ADS)

    Metairon, S.; Zamboni, C. B.; Medeiros, I. M. M. Amaral; Menezes, M. À. B. C.

    2011-08-01

    The elements concentration in the soil reference material (IAEA/SOIL-7) was obtained using the parametric Neutron Activation Analysis technique in the IEA-R1 nuclear reactor at IPEN (CNEN-SP). The results obtained were in good agreement with the respective nominal values from this reference material suggesting the viability of using this parametric procedure for environmental investigations.

  2. Reference Materials

    NASA Astrophysics Data System (ADS)

    Merkus, Henk G.

    Reference materials for measurement of particle size and porosity may be used for calibration or qualification of instruments or for validation of operating procedures or operators. They cover a broad range of materials. On the one hand there are the certified reference materials, for which governmental institutes have certified one or more typical size or porosity values. Then, there is a large group of reference materials from commercial companies. And on the other hand there are typical products in a given line of industry, where size or porosity values come from the analysis laboratory itself or from some round-robin test in a group of industrial laboratories. Their regular application is essential for adequate quality control of particle size and porosity measurement, as required in e.g., ISO 17025 on quality management. In relation to this, some quality requirements for certification are presented.

  3. Free aluminium extraction from various reference materials and acid soils with relation to plant availability.

    PubMed

    Matús, Peter; Kubová, Jana; Bujdos, Marek; Medved', Ján

    2006-12-15

    The single extractions with 15 extractants (agents) (H(2)O, KCl, NH(4)Cl, NH(4)F, CaCl(2), BaCl(2), CuCl(2), LaCl(3), Na(2)S(2)O(4), (NH(4))(2)C(2)O(4), Na(4)P(2)O(7), NTA, EDTA, DTPA, HCl), the optimised BCR (Community Bureau of Reference) three-step sequential extraction procedure (SEP) and the solid phase extraction (SPE) by the chelating ion-exchanger Iontosorb Salicyl (cellulose resin containing covalently bound salicylic acid functional groups) were used for the partitioning of Al in very acid soil samples taken from an area influenced by acid mine solutions. The precision, accuracy and repeatibility for all steps of the optimised BCR SEP were checked on the various reference materials (CRM 483 sewage sludge amended soil, CRM BCR 701 freshwater sediment, SRM 2710 and SRM 2711 Montana soils). Also the new indicative values of the optimised BCR SEP fractional Al concentrations were obtained for these reference materials. The aluminium amounts obtained by the used extraction procedures were valuated and discussed from the aspect of the Al concentration in the plants (grass) growing on the same studied soils. The aluminium toxicity indexes (ATI) calculated for the studied soils, the BaCl(2) and acetic acid soil extracts and the grass stems and roots were used for the assessment of the Al toxicity to the plants. The ATI value was defined as the ratio of the nutrient cations (Ca, Mg, K, Na) concentration sum to the Al concentration. The flame atomic absorption spectrometry (LOQ=0.2mgl(-1)) and the inductively coupled plasma optical emission spectrometry (LOQ=0.03mgl(-1)) were used for the aluminium quantification. PMID:18970873

  4. USGS reference materials

    USGS Publications Warehouse

    ,

    1995-01-01

    Every year in the United States, millions of measurements are made on the chemical composition of items that affect us on a daily basis. Determining the accuracy of these measurements is based on the analysis of appropriate reference materials whose composition was previously determined through rigorous testing. Today, reference materials help us evaluate the composition of the food we eat, medicine we use, soil we grow our crops in, and hundreds of other products that affect our everyday lives.

  5. Development of a standard reference material for Cr(vi) in contaminated soil

    USGS Publications Warehouse

    Nagourney, S.J.; Wilson, S.A.; Buckley, B.; Kingston, H.M.S.; Yang, S.-Y.; Long, S.E.

    2008-01-01

    Over the last several decades, considerable contamination by hexavalent chromium has resulted from the land disposal of Chromite Ore Processing Residue (COPR). COPR contains a number of hexavalent chromium-bearing compounds that were produced in high temperature industrial processes. Concern over the carcinogenic potential of this chromium species, and its environmental mobility, has resulted in efforts to remediate these waste sites. To provide support to analytical measurements of hexavalent chromium, a candidate National Institute of Standards and Technology (NIST) Standard Reference Material?? (SRM 2701), having a hexavalent chromium content of approximately 500 mg kg -1, has been developed using material collected from a waste site in Hudson County, New Jersey, USA. The collection, processing, preparation and preliminary physico-chemical characterization of the material are discussed. A two-phase multi-laboratory testing study was carried out to provide data on material homogeneity and to assess the stability of the material over the duration of the study. The study was designed to incorporate several United States Environmental Protection Agency (USEPA) determinative methods for hexavalent chromium, including Method 6800 which is based on speciated isotope dilution mass spectrometry (SIDMS), an approach which can account for chromium species inter-conversion during the extraction and measurement sequence. This journal is ?? The Royal Society of Chemistry 2008.

  6. Improvement of the BCR three step sequential extraction procedure prior to the certification of new sediment and soil reference materials.

    PubMed

    Rauret, G; López-Sánchez, J F; Sahuquillo, A; Rubio, R; Davidson, C; Ure, A; Quevauviller, P

    1999-02-01

    The Standards, Measurements and Testing Programme (formerly BCR) of the European Commission proposed a three-step sequential extraction procedure for sediment analysis, following extensive expert consultations and two interlaboratory studies. This scheme was recently used to certify the extractable trace element contents of a sediment reference material (CRM 601). Although this procedure offers a means to ensure the comparability of data in this field, some difficulties concerning the interlaboratory reproducibility still remain, and a new project is currently being conducted to determine the causes of poor reproducibility in the extraction scheme. The final objective of the project is the certification of new sediment and soil reference materials for their extractable contents of Cd, Cr, Cu, Ni, Pb and Zn. This paper presents the results of a small-scale interlaboratory study, which aimed to test a revised version of the extraction schemes by comparing the original and the modified protocols using the CRM 601 sample. This work offers an improvement to the BCR sequential extraction procedure through intercomparison exercises. This improved procedure will allow the obtaining of CRMs to validate analytical data in the analysis of soils and sediments, and it will also facilitate comparability of data in the European Union.

  7. Comparison of quantification methods to measure fire-derived (black/elemental) carbon in soils and sediments using reference materials from soil, water, sediment and the atmosphere

    NASA Astrophysics Data System (ADS)

    Hammes, Karen; Schmidt, Michael W. I.; Smernik, Ronald J.; Currie, Lloyd A.; Ball, William P.; Nguyen, Thanh H.; Louchouarn, Patrick; Houel, Stephane; Gustafsson, Örjan; Elmquist, Marie; Cornelissen, Gerard; Skjemstad, Jan O.; Masiello, Caroline A.; Song, Jianzhong; Peng, Ping'an; Mitra, Siddhartha; Dunn, Joshua C.; Hatcher, Patrick G.; Hockaday, William C.; Smith, Dwight M.; Hartkopf-Fröder, Christoph; BöHmer, Axel; Lüer, Burkhard; Huebert, Barry J.; Amelung, Wulf; Brodowski, Sonja; Huang, Lin; Zhang, Wendy; Gschwend, Philip M.; Flores-Cervantes, D. Xanat; Largeau, Claude; Rouzaud, Jean-NoëL.; Rumpel, Cornelia; Guggenberger, Georg; Kaiser, Klaus; Rodionov, Andrei; Gonzalez-Vila, Francisco J.; Gonzalez-Perez, José A.; de La Rosa, José M.; Manning, David A. C.; López-CapéL, Elisa; Ding, Luyi

    2007-09-01

    to provide a basis on which to choose between the different BC quantification methods in soil and sediment studies. In this paper we summarize the advantages and disadvantages of each method. In future studies, we strongly recommend the evaluation of all methods analyzing for BC in soils and sediments against the set of BC reference materials analyzed here.

  8. Isotope reference materials

    USGS Publications Warehouse

    Coplen, Tyler B.

    2010-01-01

    Measurement of the same isotopically homogeneous sample by any laboratory worldwide should yield the same isotopic composition within analytical uncertainty. International distribution of light element isotopic reference materials by the International Atomic Energy Agency and the U.S. National Institute of Standards and Technology enable laboratories to achieve this goal.

  9. Certification of a reference material for determination of total cyanide in soil to support implementation of the International Standard ISO 11262:2011.

    PubMed

    Scharf, Holger; Bremser, Wolfram

    2015-04-01

    Cyanides are among the most important inorganic pollutants to be tested and monitored in environmental compartments. They can be distinguished and determined as free cyanide, weak acid dissociable cyanide or as total cyanide. However, in any case obtained, measurement results are operationally defined referring to the applied analytical method. In 2011, the International Standard ISO 11262 has been published which specifies a normative analytical method for the determination of total cyanide in soil. The objective of the project described in this paper was to provide the first soil reference material (CRM) certified for its mass fraction of total cyanide on the basis of this standard. A total of 12 German laboratories with proven experience in the determination of cyanides in environmental samples participated in the certification study. Measurement results were evaluated in full compliance with the requirements of ISO Guide 35. Taking into account the results of the inter-laboratory comparison as well as the outcome of the homogeneity and stability studies, a certified mass fraction of total cyanide of 21.1 mg/kg and an expanded uncertainty (k = 2) of 1.3 mg/kg were assigned to the material. The reference material has been issued as CRM BAM-U114.

  10. Reference Material for Seebeck Coefficients

    NASA Astrophysics Data System (ADS)

    Edler, F.; Lenz, E.; Haupt, S.

    2015-03-01

    This paper describes a measurement method and a measuring system to determine absolute Seebeck coefficients of thermoelectric bulk materials with the aim of establishing reference materials for Seebeck coefficients. Reference materials with known thermoelectric properties are essential to allow a reliable benchmarking of different thermoelectric materials for application in thermoelectric generators to convert thermal into electrical energy or vice versa. A temperature gradient (1 to 8) K is induced across the sample, and the resulting voltage is measured by using two differential Au/Pt thermocouples. On the basis of the known absolute Seebeck coefficients of Au and Pt, the unknown Seebeck coefficient of the sample is calculated. The measurements are performed in inert atmospheres and at low pressure (30 to 60) mbar in the temperature range between 300 K and 860 K. The measurement results of the Seebeck coefficients of metallic and semiconducting samples are presented. Achievable relative measurement uncertainties of the Seebeck coefficient are on the order of a few percent.

  11. Criminal Justice - Selected Reference Materials.

    ERIC Educational Resources Information Center

    McClure, John D., III, Comp.

    This bibliography reviews approximately 70 reference materials on criminal justice. Entries are presented in eight categories--dictionaries, indexes and abstracts, professional position papers, working conditions and unions, law and the police, crime, prisons and prisoners, and victimization. Types of publications included under the subject…

  12. Differences in soil solution chemistry between soils amended with nanosized CuO or Cu reference materials: implications for nanotoxicity tests.

    PubMed

    McShane, Heather V A; Sunahara, Geoffrey I; Whalen, Joann K; Hendershot, William H

    2014-07-15

    Soil toxicity tests for metal oxide nanoparticles often include micrometer-sized oxide and metal salt treatments to distinguish between toxicity from nanometer-sized particles, non-nanometer-sized particles, and dissolved ions. Test result will be confounded if each chemical form has different effects on soil solution chemistry. We report on changes in soil solution chemistry over 56 days-the duration of some standard soil toxicity tests-in three soils amended with 500 mg/kg Cu as nanometer-sized CuO (nano), micrometer-sized CuO (micrometer), or Cu(NO3)2 (salt). In the CuO-amended soils, the log Cu2+ activity was initially low (minimum -9.48) and increased with time (maximum -5.20), whereas in the salt-amended soils it was initially high (maximum -4.80) and decreased with time (minimum -6.10). The Cu2+ activity in the nano-amended soils was higher than in the micrometer-amended soils for at least the first 11 days, and lower than in the salt-amended soils for at least 28 d. The pH, and dissolved Ca and Mg concentrations in the CuO-amended soils were similar, but the salt-amended soils had lower pH for at least 14 d, and higher Ca and Mg concentrations throughout the test. Soil pretreatments such as leaching and aging prior to toxicity tests are suggested.

  13. Estimation of mercury speciation in soil standard reference materials with different extraction methods by ion chromatography coupled with ICP-MS.

    PubMed

    Park, Misun; Yoon, Hyeon; Yoon, Cheolho; Yu, Jae-Young

    2011-01-01

    Analytical methods for the speciation of mercury, based on microwave extraction and sonication extraction, have been tested to determine the inorganic mercury and methyl mercury contents in two standard soil reference materials: SRM 2710 Montana Soil and BCR 580 estuarine sediment. Prior to applying the speciation extraction methods, the mineral compositions were analyzed via XRD analysis, with SRM 2710 shown to be composed mostly of aluminum silicate minerals, while carbonate minerals were the major constituent in BCR 580. Two extraction methods, microwave and sonication, were tested for the analysis and recovery efficiency of total mercury. The accuracy and efficiency of each extraction method was also compared. In the analysis of total mercury, the microwave extraction method, with using methanol and HCl as extractants, was better for SRM2710, while the application of the sonication extraction method was more efficient for the calcite-based BCR 580. The results showed good separation and recovery efficiencies, with values reaching 100% of those estimated. The sonication method was selected for the speciation of mercury, especially in BCR 580. An extraction solution comprising of a 1:1 mixture of methanol and HCl was used for the sonication extraction of BCR 580, with the resulting extractants analyzed by IC-HG-ICP-MS for methyl mercury and inorganic mercury. As a simple, rapid, sensitive, and accurate method, sonication extraction was found to be satisfactory.

  14. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have...

  15. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have...

  16. Reference materials for cellular therapeutics.

    PubMed

    Bravery, Christopher A; French, Anna

    2014-09-01

    The development of cellular therapeutics (CTP) takes place over many years, and, where successful, the developer will anticipate the product to be in clinical use for decades. Successful demonstration of manufacturing and quality consistency is dependent on the use of complex analytical methods; thus, the risk of process and method drift over time is high. The use of reference materials (RM) is an established scientific principle and as such also a regulatory requirement. The various uses of RM in the context of CTP manufacturing and quality are discussed, along with why they are needed for living cell products and the analytical methods applied to them. Relatively few consensus RM exist that are suitable for even common methods used by CTP developers, such as flow cytometry. Others have also identified this need and made proposals; however, great care will be needed to ensure any consensus RM that result are fit for purpose. Such consensus RM probably will need to be applied to specific standardized methods, and the idea that a single RM can have wide applicability is challenged. Written standards, including standardized methods, together with appropriate measurement RM are probably the most appropriate way to define specific starting cell types. The characteristics of a specific CTP will to some degree deviate from those of the starting cells; consequently, a product RM remains the best solution where feasible. Each CTP developer must consider how and what types of RM should be used to ensure the reliability of their own analytical measurements.

  17. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C 552(a) and 1 CFR part 51. Material is... information only and may not be all inclusive. Source and name of material 49 CFR reference Air Transport... sections in which the material is referenced. Source and name of material 49 CFR reference...

  18. Reference materials for new psychoactive substances.

    PubMed

    Archer, Roland P; Treble, Ric; Williams, Keith

    2011-01-01

    Historically, the appearance of new psychoactive materials (and hence the requirement for new reference standards) has been relatively slow. This position has now changed, with 101 new psychoactive substances reported to EMCDDA-Europol since 2006. The newly reported materials, and associated metabolites, require properly certified reference materials to permit reliable identification and quantification. The traditional approach and timescales of reference material production and certification are being increasingly challenged by the appearance of these new substances. Reference material suppliers have to adopt new strategies to meet the needs of laboratories. This situation is particularly challenging for toxicology standards as the metabolism of many of these substances is initially unknown. Reference material production often involves synthesis from first principles. While it is possible to synthesis these materials, there can be significant difficulties, from synthetic complexities through to the need to use controlled materials. These issues are examined through a discussion of the synthesis of cathinones. Use of alternative sources, including pharmaceutical impurity materials or internet sourced products, as starting materials for conversion into appropriately certified reference materials are also discussed. The sudden appearance and sometimes brief lifetime in the market place of many of these novel legal highs or research chemicals present commercial difficulties for reference material producers. The need for collaboration at all levels is highlighted as essential to rapid identification of requirements for new reference materials. National or international commissioning or support may also be required to permit reference material producers to recover their development costs. PMID:21744516

  19. Bisphenol A polycarbonate as a reference material

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Cumming, H. J.; Williams, J. B.

    1977-01-01

    Test methods require reference materials to standardize and maintain quality control. Various materials have been evaluated as possible reference materials, including a sample of bisphenol A polycarbonate without additives. Screening tests for relative toxicity under various experimental conditions were performed using male mice exposed to pyrolysis effluents over a 200-800 C temperature range. It was found that the bisphenol A polycarbonate served as a suitable reference material as it is available in large quantities, and does not significantly change with time.

  20. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... incorporation by reference by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR..., into § 173.417. (2) Table 1 to 49 CFR 171.7—Materials Not Incorporated by Reference Source and name of material 49 CFR reference American Biological Safety Association 1202 Allanson Road, Mundelein, IL...

  1. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... incorporation by reference by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR..., amendment 1 (2011). Table 1 to 49 CFR 171.7—Materials Not Incorporated by Reference Source and name of material 49 CFR reference American Biological Safety Association 1202 Allanson Road, Mundelein, IL...

  2. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air and Radiation... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference...

  3. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air and Radiation... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference...

  4. The need for new isotope reference materials.

    PubMed

    Vogl, Jochen; Rosner, Martin; Pritzkow, Wolfgang

    2013-03-01

    Isotope reference materials are needed to calibrate and validate analytical procedures used for the determination of isotope amount ratios, procedurally defined isotope ratios or so-called δ values. In contrast to the huge analytical progress in isotope ratio analytics, the production of isotope reference materials has not kept pace with the increasing needs of isotope analysts. Three representative isotope systems are used to explain the technical and non-technical difficulties and drawbacks, on one hand, and to demonstrate what can be achieved at its best, on the other hand. A clear statement is given that new isotope reference materials are needed to obtain traceable and thus comparable data, which is essential for all kinds of isotope research. The range of available isotope reference materials and δ reference materials should be increased and matrix reference materials certified for isotope compositions or δ values, which do not exist yet, should be provided.

  5. 40 CFR 1066.710 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Practice for Measuring Fuel Economy and Emissions of Hybrid-Electric and Conventional Heavy-Duty Vehicles... VEHICLE-TESTING PROCEDURES Definitions and Other Reference Material § 1066.710 Reference materials. (a... Federal Register under 5 U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other than that...

  6. Performance criteria for reference measurement procedures and reference materials.

    PubMed

    Schimmel, Heinz; Zegers, Ingrid

    2015-05-01

    The concept of metrological traceability of measurement results to property values assigned to measurement standards of higher metrological order or to the International System of Units (SI) through sequential calibrations, using reference materials and reference measurement procedures, plays a key role in ensuring that end user measurement procedures perform at an acceptable level in the clinical context. The aim is that measurement results produced over time or by different end users or with different end user measurement procedures for the same measurand will be equivalent within their corresponding uncertainties. These goals can only be reached under certain conditions and if requirements laid down in international standards on calibration concepts, reference measurement procedures and reference materials are fulfilled. Calibration hierarchies have to be implemented correctly and parameters contributing to measurement uncertainty and systematic bias need to be controlled and eliminated, respectively, by technically improving methods and reference materials and intermediate calibrators used for effectively achieving equivalence of measurement results and for meeting analytical performance requirements for in vitro diagnostic devices.

  7. Analysis of standard reference materials by absolute INAA

    SciTech Connect

    Heft, R.E.; Koszykowski, R.F.

    1981-07-01

    Three standard reference materials, flyash, soil, and ASI 4340 steel, were analyzed by a method of absolute instrumental neutron activation analysis (INAA). Two different light water pool-type reactors were used to produce equivalent analytical results even though the epithermal to thermal flux ratio in one reactor was higher than that in the other by a factor of two.

  8. 40 CFR 94.5 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air...: Table 2 of § 94.5—ISO Materials Document No. and name 40 CFR part 94 reference ISO 8178-1, Reciprocating... name 40 CFR part 94 reference Resolution 2—Technical Code on Control of Emission of Nitrogen...

  9. 40 CFR 94.5 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air...: Table 2 of § 94.5—ISO Materials Document No. and name 40 CFR part 94 reference ISO 8178-1, Reciprocating... name 40 CFR part 94 reference Resolution 2—Technical Code on Control of Emission of Nitrogen...

  10. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C 552(a) and 1 CFR part 51. Material is... information only and may not be all inclusive. Source and name of material 49 CFR reference Air Transport... for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless 173.5b. ASTM A 106, ASTM A...

  11. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C 552(a) and 1 CFR part 51. Material is... information only and may not be all inclusive. Source and name of material 49 CFR reference Air Transport... for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless 173.5b. ASTM A 106, ASTM A...

  12. Reading Materials in Large Type. Reference Circular.

    ERIC Educational Resources Information Center

    Ovenshire, Ruthann, Comp.

    Listed in the circular are approximately 32 commercial and volunteer producers of large type materials, approximately 50 large type books for reference and special needs, and five further sources of large type materials. Usually given for each alphabetically listed producer are the address, specialty (whether producer of specific categories or of…

  13. Polyfluorinated substances in abiotic standard reference materials

    EPA Science Inventory

    The National Institute of Standards and Technology (NIST) has a wide range of Standard Reference Materials (SRMs) which have values assigned for legacy organic pollutants and toxic elements. Existing SRMs serve as homogenous materials that can be used for method development, meth...

  14. Myths of Isotopic Reference Materials Busted

    NASA Astrophysics Data System (ADS)

    Coplen, T.

    2007-12-01

    During the past several years, the determination of the isotopic abundances of elements including H, Li, B, C, N, O, Mg, Si, S, Cl, Ca, Cr, Fe, Cu, Zn, Tl, and Se has substantially increased because of expanded use in hydrology, environmental studies, microbiology, forensic investigations, atmospheric investigations, oceanography, etc. Improvements in instrumentation enable increasingly precise isotope-amount-ratio measurements in these fields, but these improvements in precision commonly do not lead to improvements in accuracy because of the lack or improper use of isotopic reference materials. When properly used, these critically important materials enable any laboratory worldwide to measure the same homogeneous sample and report the same isotopic abundance within analytical uncertainty. For example, for stable isotopic analysis of gaseous hydrogen samples, the agreement among 36 laboratories worldwide before normalization to any hydrogen gas reference material was 11.8 per mill. After normalization to anchors (gaseous H isotopic reference materials) at each end of the delta H-2 scale, the agreement was 0.85 per mill, an improvement of more than an order of magnitude. Consistency of delta C-13 measurements often can be improved by nearly 50 percent by anchoring the delta C-13 scale with two isotopic reference materials differing substantially in C-13 mole fraction, namely NBS 19 calcite and L-SVEC lithium carbonate. Agreement of delta C-13 values of four expert laboratories analyzing USGS40 L- glutamic acid by CF-IRMS methods improved from 0.084 to 0.015 per mill with use of the two scale anchors (NBS 19 and L-SVEC). Solid oxygen isotopic reference materials (IAEA-600 caffeine, IAEA-601 and IAEA-602 benzoic acids, IAEA-NO-3, USGS32, USGS34, and USGS35 nitrates, NBS-127, IAEA-SO-5, and IAEA-SO-6 barium sulfates) are poorly calibrated. Calibrating these solids to the VSMOW-SLAP reference water scale has been very difficult because both the solids and reference

  15. Soil Conservation Unit for the Advanced Crop Production and Marketing Course. Student Reference. AGDEX 570.

    ERIC Educational Resources Information Center

    Stewart, Bob R.; And Others

    This student reference booklet is designed to accompany lessons outlined in the companion instructor's guide on soil conservation. The soil conservation unit builds on competencies gained in Agricultural Science I and II. Informative material is provided for these eight lessons: benefits of conservation, land utilization, how soils are eroded,…

  16. Reference Materials on the World Wide Web.

    ERIC Educational Resources Information Center

    Kitao, Kenji

    2002-01-01

    This paper presents information about World Wide Web resources for English language teachers and students and for communication scholars and researchers. The first Web page, "Reference Materials for Students and Researchers," offers links to resources in English. Because there are many Web sites related to dictionaries, a second page, "Reference…

  17. 40 CFR 86.1 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone... § 86.1901. (2) (g) Society of Automotive Engineers (SAE). Anyone may purchase copies of these materials from Society of Automotive Engineers, 400 Commonwealth Dr., Warrendale, PA 15096-0001, (877)...

  18. 40 CFR 1065.1010 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 4 of this section lists material from the Society of Automotive Engineering that we have... Federal Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part... Specification for Automotive Spark-Ignition Engine Fuel 1065.701 ASTM D5186-03, Standard Test Method...

  19. A new basaltic glass microanalytical reference material for multiple techniques

    USGS Publications Warehouse

    Wilson, Steve; Koenig, Alan; Lowers, Heather

    2012-01-01

    The U.S. Geological Survey (USGS) has been producing reference materials since the 1950s. Over 50 materials have been developed to cover bulk rock, sediment, and soils for the geological community. These materials are used globally in geochemistry, environmental, and analytical laboratories that perform bulk chemistry and/or microanalysis for instrument calibration and quality assurance testing. To answer the growing demand for higher spatial resolution and sensitivity, there is a need to create a new generation of microanalytical reference materials suitable for a variety of techniques, such as scanning electron microscopy/X-ray spectrometry (SEM/EDS), electron probe microanalysis (EPMA), laser ablation inductively coupled mass spectrometry (LA-ICP-MS), and secondary ion mass spectrometry (SIMS). As such, the microanalytical reference material (MRM) needs to be stable under the beam, be homogeneous at scales of better than 10–25 micrometers for the major to ultra-trace element level, and contain all of the analytes (elements or isotopes) of interest. Previous development of basaltic glasses intended for LA-ICP-MS has resulted in a synthetic basaltic matrix series of glasses (USGS GS-series) and a natural basalt series of glasses (BCR-1G, BHVO-2G, and NKT-1G). These materials have been useful for the LA-ICP-MS community but were not originally intended for use by the electron or ion beam community. A material developed from start to finish with intended use in multiple microanalytical instruments would be useful for inter-laboratory and inter-instrument platform comparisons. This article summarizes the experiments undertaken to produce a basalt glass reference material suitable for distribution as a multiple-technique round robin material. The goal of the analytical work presented here is to demonstrate that the elemental homogeneity of the new glass is acceptable for its use as a reference material. Because the round robin exercise is still underway, only

  20. SOIL VAPOR EXTRACTION TECHNOLOGY: REFERENCE HANDBOOK

    EPA Science Inventory

    Soil vapor extraction (SVE) systems are being used in Increasing numbers because of the many advantages these systems hold over other soil treatment technologies. SVE systems appear to be simple in design and operation, yet the fundamentals governing subsurface vapor transport ar...

  1. High Precision Isotopic Reference Material Program

    NASA Astrophysics Data System (ADS)

    Mann, J. L.; Vocke, R. D.

    2007-12-01

    Recent developments in thermal ionization and inductively coupled plasma multicollector mass spectrometers have lead to "high precision" isotope ratio measurements with uncertainties approaching a few parts in 106. These new measurement capabilities have revolutionized the study of isotopic variations in nature by increasing the number of elements showing natural variations by almost a factor of two, and new research areas are actively opening up in climate change, health, ecology, geology and forensic studies. Because the isotopic applications are impacting very diverse fields, there is at present little effective coordination between research laboratories over reference materials and the values to apply to those materials. NIST had originally developed the techniques for producing accurate isotopic characterizations, culminating in the NIST Isotopic SRM series. The values on existing materials however are insufficiently precise and, in some cases, may be isotopically heterogeneous. A new generation of isotopic standards is urgently needed and will directly affect the quality and scope of emergent applications and ensure that the results being derived from these diverse fields are comparable. A series of new isotopic reference materials similar to the NIST 3100 single element solution series is being designed for this purpose and twelve elements have been selected as having the most pressing need. In conjunction with other expert users and National Metrology Institutes, an isotopic characterization of the respective 12 selected ampoules from the NIST single element solution series is currently underway. In this presentation the preliminary results of this screening will be discussed as well as the suitability of these materials in terms of homogeneity and purity, long term stability and availability, and isotopic relevance. Approaches to value assignment will also be discussed.

  2. Thermoelectric standardisation - Reference materials and characterisation

    NASA Astrophysics Data System (ADS)

    Ziolkowski, P.; Blaschkewitz, P.; Stiewe, C.; Karpinski, G.; Müller, E.

    2012-06-01

    Thermoelectric materials for working temperatures between 300 K and 1000 K become continuously more important for energy recuperation applications. The efficiency is determined by the transport properties (electrical and thermal conductivity and Seebeck coefficient), which form the known thermoelectric figure of merit ZT. The thorough determination of ZT represents the basis for the assessment of thermoelectric materials research. Due to different continuing difficulties measurement errors distinctly higher than 15% can be observed repeatedly, which is still too high for an industrial benchmark and deficient for many scientific investigations and technological developments. Against this background a project was launched in 2011 together with the Fraunhofer Institute of Physical Measurement Techniques (IPM, Freiburg), the Department Temperature of the Physikalisch-Technische Bundesanstalt (PTB, Berlin) and the company Netzsch Gerätebau GbmH (Selb). The aim of the project "Thermoelectric Standardisation" (TEST) is to minimise the measurement uncertainties and to develop traceable, high-accurate thermoelectric characterisation techniques and thermoelectric reference materials for the mentioned temperature range. Here we initially present the project to the thermoelectric society and want to give a survey on the planned activities and the current status of the contributions of the German Aerospace Center (DLR, Cologne).

  3. Value assignment of nutrient concentrations in five standard reference materials and six reference materials.

    PubMed

    Sharpless, K E; Gill, L M

    2000-01-01

    A number of food-matrix reference materials (RMs) are available from the National Institute of Standards and Technology (NIST) and from Agriculture Canada through NIST. Most of these materials were originally value-assigned for their elemental composition (major, minor, and trace elements), but no additional nutritional information was provided. Two of the materials were certified for selected organic constituents. Ten of these materials (Standard Reference Material [SRM] 1,563 Cholesterol and Fat-Soluble Vitamins in Coconut Oil [Natural and Fortified], SRM 1,566b Oyster Tissue, SRM 1,570a Spinach Leaves, SRM 1,974a Organics in Mussel Tissue (Mytilus edulis), RM 8,415 Whole Egg Powder, RM 8,418 Wheat Gluten, RM 8,432 Corn Starch, RM 8,433 Corn Bran, RM 8,435 Whole Milk Powder, and RM 8,436 Durum Wheat Flour) were recently distributed by NIST to 4 laboratories with expertise in food analysis for the measurement of proximates (solids, fat, protein, etc.), calories, and total dietary fiber, as appropriate. SRM 1846 Infant Formula was distributed as a quality control sample for the proximates and for analysis for individual fatty acids. Two of the materials (Whole Egg Powder and Whole Milk Powder) were distributed in an earlier interlaboratory comparison exercise in which they were analyzed for several vitamins. Value assignment of analyte concentrations in these 11 SRMs and RMs, based on analyses by the collaborating laboratories, is described in this paper. These materials are intended primarily for validation of analytical methods for the measurement of nutrients in foods of similar composition (based on AOAC INTERNATIONAL's fat-protein-carbohydrate triangle). They may also be used as "primary control materials" in the value assignment of in-house control materials of similar composition. The addition of proximate information for 10 existing reference materials means that RMs are now available from NIST with assigned values for proximates in 6 of the 9 sectors of

  4. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA Air and Radiation... 19103. Document number and name 40 CFR part 90 reference ASTM D86-93: Standard Test Method for...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September...

  5. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA Air and Radiation... 19103. Document number and name 40 CFR part 90 reference ASTM D86-93: Standard Test Method for...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September...

  6. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA, OAR, Air and Radiation Docket and... 19103. Document number and name 40 CFR part 91 reference ASTM D86-93: Standard Test Method for... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine...

  7. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA, OAR, Air and Radiation Docket and... 19103. Document number and name 40 CFR part 91 reference ASTM D86-93: Standard Test Method for... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine...

  8. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA, OAR, Air and Radiation Docket and... 19103. Document number and name 40 CFR part 91 reference ASTM D86-93: Standard Test Method for... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine...

  9. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA Air and Radiation... 19103. Document number and name 40 CFR part 90 reference ASTM D86-93: Standard Test Method for...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September...

  10. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA Air and Radiation... 19103. Document number and name 40 CFR part 90 reference ASTM D86-93: Standard Test Method for...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September...

  11. 40 CFR 92.5 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected...., Philadelphia, PA 19103. The table follows: Document number and name 40 CFR part 92 reference ASTM D 86-95... follows: Document number and name 40 CFR part 92 reference SAE Paper 770141, Optimization of a...

  12. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA, OAR, Air and Radiation Docket and... 19103. Document number and name 40 CFR part 91 reference ASTM D86-93: Standard Test Method for... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine...

  13. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA Air and Radiation... 19103. Document number and name 40 CFR part 90 reference ASTM D86-93: Standard Test Method for...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September...

  14. 40 CFR 92.5 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected...., Philadelphia, PA 19103. The table follows: Document number and name 40 CFR part 92 reference ASTM D 86-95... follows: Document number and name 40 CFR part 92 reference SAE Paper 770141, Optimization of a...

  15. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...(a) and 1 CFR part 51. Copies may be inspected at U.S. EPA, OAR, Air and Radiation Docket and... 19103. Document number and name 40 CFR part 91 reference ASTM D86-93: Standard Test Method for... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine...

  16. 40 CFR 1065.1010 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Federal Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part... of the International System of Units (SI), Barry N. Taylor, Physics Laboratory 1065.20,...

  17. 40 CFR 89.6 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at US EPA, OAR, 1200 Pennsylvania Ave... 19428-2959. Document number and name 40 CFR part 89 reference ASTM D86-97: “Standard Test Method for... Commonwealth Dr., Warrendale, PA 15096-0001. Document number and name 40 CFR part 89 reference SAE J244 June...

  18. 40 CFR 89.6 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at US EPA, OAR, 1200 Pennsylvania Ave... 19428-2959. Document number and name 40 CFR part 89 reference ASTM D86-97: “Standard Test Method for... Commonwealth Dr., Warrendale, PA 15096-0001. Document number and name 40 CFR part 89 reference SAE J244 June...

  19. Reference materials and intercomparison samples available from the Environmental Monitoring Systems Laboratory - Las Vegas

    SciTech Connect

    Kantor, E.J.; Laska, P.R.

    1985-06-01

    Reference materials and intercomparison samples may be obtained by laboratories involved in the analysis of environmental samples containing radioactivity, pesticides, toxic inorganic species, or toxic organic species. These reference materials and intercomparison samples are available from the US Environmental Protection Agency's Quality Assurance Division located at the Environmental Monitoring Systems Laboratory in Las Vegas (EMSL-LV). These materials are useful for incorporation into a laboratory's quality control program for the evaluation of the precision and accuracy of analytical work. Media used for radiation reference materials are pitchblende, Monazite ore, uranium mill tailings, Mancos shale, fly ash, and water spiked with radionuclides. Radioactivity intercomparison samples consist of water, milk, air, urine, and a simulated diet slurry spiked with radionuclides. Media available for toxic organic reference materials are sludge, shale oil, and rag oil, and for intercomparison samples are soil and water. Characterized fly ash, foundry sludge, and river sediment serve as reference materials for toxic inorganics, while spiked soil and water serve as intercomparison samples. Finally, spiked adipose tissue, blood plasma, urine, and water comprise the pesticide intercomparison samples, and, after the disclosure of the true pesticide compositions and concentrations of these samples, the laboratory can use the samples as reference materials. The reference materials are generally available continuously, but the intercomparison samples are distributed on a scheduled basis and in some cases only to certain laboratories. 9 tables.

  20. Reproducibility of polycarbonate reference material in toxicity evaluation

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Huttlinger, P. A.

    1981-01-01

    A specific lot of bisphenol A polycarbonate has been used for almost four years as the reference material for the NASA-USF-PSC toxicity screening test method. The reproducibility of the test results over this period of time indicate that certain plastics may be more suitable reference materials than the more traditional cellulosic materials.

  1. Expanded Subject Access to Reference Collection Materials.

    ERIC Educational Resources Information Center

    Mischo, William H.

    1979-01-01

    Reports a computer assisted index emphasizing expanded subject access to the reference collection of the Iowa State University Library. The index displays abbreviated length records and complements existing catalogs. Limitations of subject access and a system for assigning subject descriptors are discussed. (Author/RAA)

  2. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air... Embankment, London SE1 7SR, United Kingdom, or http://www.imo.org, or 44-(0)20-7735-7611. (1) Revised...

  3. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air... Embankment, London SE1 7SR, United Kingdom, or http://www.imo.org, or 44-(0)20-7735-7611. (1) Revised...

  4. AOAC INTERNATIONAL's Technical Division on Reference Materials (TDRM) Reference Materials Database.

    PubMed

    Zink, Donna

    2016-09-01

    The Technical Division on Reference Materials (TDRM) of AOAC INTERNATIONAL recommends policy and criteria to facilitate the development and use of reference materials (RMs) in the validation, implementation, and routine use of AOAC INTERNATIONAL methods. To aid analysts in these areas, TDRM has developed a searchable online database to identify RMs suitable for use with AOAC Official Methods of Analysis(SM) (OMA). RMs can be queried by analyte, by analyte and matrix, or by the selection of an OMA, based on analytes and matrixes described within the scope of the selected method. Only essential information is included in the database, to maximize usefulness and minimize the effort required to keep information current. Additional information, such as measurement uncertainty and purchasing instructions, is available through a link to the producer's Web site, when that information is available online. Data sets are solicited on a voluntary basis from National Metrology Institutes and accredited producers. Consideration of ease-of-use and ease-of-operation is a guiding principle in this database, as is cost management. PMID:27619655

  5. Corrosion reference for geothermal downhole materials selection

    SciTech Connect

    Ellis, P.F. II, Smith, C.C.; Keeney, R.C.; Kirk, D.K.; Conover, M.F.

    1983-03-01

    Geothermal downhole conditions that may affect the performance and reliability of selected materials and components used in the drilling, completion, logging, and production of geothermal wells are reviewed. The results of specific research and development efforts aimed at improvement of materials and components for downhole contact with the hostile physicochemical conditions of the geothermal reservoir are discussed. Materials and components covered are tubular goods, stainless steels and non-ferrous metals for high-temperature downhole service, cements for high-temperature geothermal wells, high-temperature elastomers, drilling and completion tools, logging tools, and downhole pumps. (MHR)

  6. 15 CFR 200.104 - Standard reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., PROCEDURES, AND FEES § 200.104 Standard reference materials. Often the performance of a device or structure...-characterized materials that are needed to calibrate a measurement system or to produce scientific data that...

  7. 40 CFR 86.1 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Director of the Federal Register under 5 U.S.C. 552(a) and 1 CFR part 51. To enforce any edition other than... materials may be obtained from Society of Automotive Engineers International, 400 Commonwealth Dr..., Methane Measurement Using Gas Chromatography, 1994 SAE Handbook—SAE International Cooperative...

  8. 10 CFR 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Materials incorporated by reference. 431.105 Section 431.105 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... Storage Tanks Test Procedures § 431.105 Materials incorporated by reference. (a) General. DOE...

  9. 10 CFR 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.105 Section 431.105 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... Storage Tanks Test Procedures § 431.105 Materials incorporated by reference. (a) The...

  10. 10 CFR 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.105 Section 431.105 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... Storage Tanks Test Procedures § 431.105 Materials incorporated by reference. (a) General. DOE...

  11. Corrosion reference for geothermal downhole materials selection: Overview

    SciTech Connect

    Ellis, Peter F.

    1982-10-08

    A consolidated reference of materials for downhole equipment used in geothermal energy exploitation is nearing completion. The reference is a summary of recent developments in the areas of tubular goods materials, highly alloyed metals, high temperature cements, high temperature elastomers, drilling and completion tools, logging tools, and downwell pumps. A brief overview is presented in this paper.

  12. [Review of normal spectral emissivity standard reference materials].

    PubMed

    Yu, Kun; Liu, Yu-Fang; Zhao, Yue-Jin

    2012-11-01

    In order to improve the accuracy of spectral emissivity measurement, standard reference materials of spectral emissivity as the dissemination of quantity in spectral emissivity measurement are used for the calibration of spectral emissivity measurement apparatus. In the present paper, firstly the standard reference materials data proposed by the American National Institute of Standards and Technology are introduced, and some underlying standard reference materials suggested by some metering departments in Europe are analyzed in detail For the standard reference material Armco iron and SiC proposed by some researchers, the advantages and disadvantages were explored. Finally, the characteristics of standard reference materials are summarized, and the future development of spectral emissivity measurement standard is prospected.

  13. Reference values for soil structural degradation evaluation: an approach using shrinkage analysis

    NASA Astrophysics Data System (ADS)

    Johannes, Alice; Weisskopf, Peter; Schulin, Rainer; Boivin, Pascal

    2015-04-01

    Introduction Diagnosis of soil compaction and other soil structural degradation require reference threshold values defining non-degraded soil structure versus degraded soil structure. Large-scale application, e.g. for soil protection regulation, require accurate, cost-efficient and robust methods providing meaningful information with respect to soil quality. The shrinkage curve analysis (ShC)(Braudeau et al., 2004) does not only provide relevant parameters for soil functions such as water and air content of structural porosity but also holds promises to fulfil these requirements. Our objective was to test the potential of ShC analysis to define reference values for soil structural degradation at Swiss scale. Material and Methods Agricultural soils of the most common soil order on the Swiss plateau, namely cambi-luvisol, were sampled. Undisturbed samples were collected from topsoil at 200 locations from spring 2012 to fall 2014 on a large area (240 km) across Switzerland. Three types of soil managements were represented, namely permanent pasture (PP), conventional tillage and no-till. Only soils showing no evidence of structural degradation, as assessed visually and according to a VESS score smaller than 3 (Ball et al., 2007), were sampled. Compaction, erosion, waterlogging and poor degradation of organic matter were criteria to discard sampling locations. The undisturbed soil samples were analysed for SOC, texture, CEC and ShC, from which a set of parameters defining the soil porosities and hydrostructural stability was obtained. Results and Discussion The texture properties were similar between the different soil management, with clay content ranging from 10 to 35%. SOC content ranged from 0.5 to 4.5% and was significantly larger in average for PP, though the ranges were largely overlapping amongst the 3 soil managements. ShC parameters were found to be highly determined by SOC, with the R2 of the regressions usually over 70%, regardless of soil management, large

  14. ISOTOPIC COMPOSITIONS OF URANIUM REFERENCE MATERIALS

    SciTech Connect

    Jacobsen, B; Borg, L; Williams, R; Brennecka, G; Hutcheon, I

    2009-09-03

    Uranium isotopic compositions of a variety of U standard materials were measured at Lawrence Livermore National Laboratory and are reported here. Both thermal ionization mass spectrometry (TIMS) and multi-collector inductively couple plasma mass spectrometry (MC-ICPMS) were used to determine ratios of the naturally occurring isotopes of U. Establishing an internally coherent set of isotopic values for a range of U standards is essential for inter-laboratory comparison of small differences in {sup 238}U/{sup 235}U, as well as the minor isotopes of U. Differences of {approx} 1.3{per_thousand} are now being observed in {sup 238}U/{sup 235}U in natural samples, and may play an important role in understanding U geochemistry where tracing the origin of U is aided by U isotopic compositions. The {sup 238}U/{sup 235}U ratios were measured with a TRITON TIMS using a mixed {sup 233}U-{sup 236}U isotopic tracer to correct for instrument fractionation. this tracer was extremely pure and resulted in only very minor corrections on the measured {sup 238}U/{sup 235}U ratios of {approx} 0.03. The values obtained for {sup 238}U/{sup 235}U are: IRMM184 = 137.698 {+-} 0.020 (n = 15), SRM950a = 137.870 {+-} 0.018 (n = 8), and CRM112a = 137.866 {+-} 0.030 (n = 16). Uncertainties represent 2 s.d. of the population. The measured value for IRMM184 is in near-perfect agreement with the certified value of 137.697 {+-} 0.042. However, the U isotopic compositions of SRM950a and CRM112a are not certified. Minor isotopes of U were determined with a Nu Plasma HR MC-ICPMS and mass bias was corrected by sample/standard bracketing to IRMM184, using its certified {sup 238}U/{sup 235}U ratio. Thus, the isotopic compositions determined using both instruments are compatible. The values obtained for {sup 234}U/{sup 235}U are: SRM950a = (7.437 {+-} 0.043) x 10{sup -3} (n = 18), and CRM112a = (7.281 {+-} 0.050) x 10{sup -3} (n = 16), both of which are in good agreement with published values. The value for

  15. Teaching about Asia: Professional Materials and Reference Books.

    ERIC Educational Resources Information Center

    Hantula, James N.

    This two-part document serves as a guide to basic materials on Asia. The first part provides the teacher of Asian studies with nonserial examples of pertinent professional materials and reference books in print since 1979. Criteria used in selecting the items are given and a brief comparison between materials available in 1969 and 1985 is made.…

  16. Progress in Value Assignment for Stable Isotope Reference Materials

    NASA Astrophysics Data System (ADS)

    Gröning, M.; Taylor, P. D.; Klinedinst, D. B.

    2001-05-01

    A re-compilation of the existing certificate data for stable isotope reference materials was carried out at IAEA during the last years. Most of these isotopic ratios are expressed as per mil deviation relative to the isotopic ratio of an artificially chosen primary reference material using the commonly used conventional δ -scales. The recommended isotope values for those reference materials, produced by various researchers and institutions over the last four decades and distributed by the IAEA and NIST, have been subject to different `value assignment' approaches in the past and resulted in some inconsistencies in their recommended certified isotopic composition. During an IAEA Advisory Group meeting in September 2000 consensus was obtained on a consistent and robust a posteriori data evaluation to assign the value on the existing whole suite of stable isotope reference materials (RM) for the elements of hydrogen, carbon, nitrogen, oxygen and sulfur. Advances towards a closer calibration of carbon RMs were presented by NIST as a result of a performed calibration exercise for inorganic stable carbon RMs involving selected laboratories. For the first time sulfur stable isotope calibration data were presented by different institutions, which allow a firm and consistent value assignment of sulfur stable isotope RMs. At the same time efforts at IRMM were presented to tie up those conventional δ -scale values to SI-units by direct isotope ratio measurements using primary methods. The future challenges are twofold: 1. improving and maintaining the consistency of established stable isotope δ -scales by better characterization of existing reference materials and production of suitable successor materials (as example the primary water reference materials VSMOW and SLAP will be discussed), and 2. producing suitable reference materials for new analytical methods, especially in the field of organic compounds analyzed by means of continuous flow methods involving gas

  17. 40 CFR 194.13 - Submission of reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... COMPLIANCE WITH THE 40 CFR PART 191 DISPOSAL REGULATIONS Compliance Certification and Re-certification... and Santa Fe, New Mexico. Reference materials that are widely available in standard text books...

  18. 40 CFR 194.13 - Submission of reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... COMPLIANCE WITH THE 40 CFR PART 191 DISPOSAL REGULATIONS Compliance Certification and Re-certification... and Santa Fe, New Mexico. Reference materials that are widely available in standard text books...

  19. 40 CFR 194.13 - Submission of reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... COMPLIANCE WITH THE 40 CFR PART 191 DISPOSAL REGULATIONS Compliance Certification and Re-certification... and Santa Fe, New Mexico. Reference materials that are widely available in standard text books...

  20. Characterization of a diet reference material for 17 elements

    SciTech Connect

    Miller-Ihli, N.J.; Wolf, W.R.

    1986-12-01

    A freeze-dried diet reference material was prepared from commonly consumed everyday foods. Concentrations of major (Mg, Ca, Na, K and P), minor (Mn, Zn, Fe, Cu, and Al), and trace elements (Cr, Ni, Co, Mo, As, Se, and Cd) in this diet material were determined by the authors and 10 collaborating laboratories using a total of 10 different analytical techniques. Good agreement between concentration values determined by the different laboratories enabled the authors to computer recommended values and uncertainties for these 17 elements. Values for proximates as well as several other nutrients were also reported by collaborators. This diet material is available to the scientific community as Reference Material 8431 through the National Bureau of Standard's Office of Standard Reference Materials.

  1. Certified reference materials and reference methods for nuclear safeguards and security.

    PubMed

    Jakopič, R; Sturm, M; Kraiem, M; Richter, S; Aregbe, Y

    2013-11-01

    Confidence in comparability and reliability of measurement results in nuclear material and environmental sample analysis are established via certified reference materials (CRMs), reference measurements, and inter-laboratory comparisons (ILCs). Increased needs for quality control tools in proliferation resistance, environmental sample analysis, development of measurement capabilities over the years and progress in modern analytical techniques are the main reasons for the development of new reference materials and reference methods for nuclear safeguards and security. The Institute for Reference Materials and Measurements (IRMM) prepares and certifices large quantities of the so-called "large-sized dried" (LSD) spikes for accurate measurement of the uranium and plutonium content in dissolved nuclear fuel solutions by isotope dilution mass spectrometry (IDMS) and also develops particle reference materials applied for the detection of nuclear signatures in environmental samples. IRMM is currently replacing some of its exhausted stocks of CRMs with new ones whose specifications are up-to-date and tailored for the demands of modern analytical techniques. Some of the existing materials will be re-measured to improve the uncertainties associated with their certified values, and to enable laboratories to reduce their combined measurement uncertainty. Safeguards involve the quantitative verification by independent measurements so that no nuclear material is diverted from its intended peaceful use. Safeguards authorities pay particular attention to plutonium and the uranium isotope (235)U, indicating the so-called 'enrichment', in nuclear material and in environmental samples. In addition to the verification of the major ratios, n((235)U)/n((238)U) and n((240)Pu)/n((239)Pu), the minor ratios of the less abundant uranium and plutonium isotopes contain valuable information about the origin and the 'history' of material used for commercial or possibly clandestine purposes, and

  2. 10 CFR 431.263 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... paragraph (b) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to this material by the standard-setting organization will not affect... Society for Testing and Materials (ASTM) Standard F2324-03, “Standard Test Method for Prerinse...

  3. Preparation and characterization of ``exhausted electrowinning electrolyte'' reference material

    NASA Astrophysics Data System (ADS)

    Arana, G.; Amigo, J. M.; Etxebarria, N.; Fernandez, L. A.; Raposo, J. C.

    2003-05-01

    The number of available reference materials of complex matrices is continuously growing but it is still far from ideal. There are too many different matrices which are of interest for too many different analytes. The certified reference materials are expensive and are intended for the validation of methods or for the assurance of traceability of the analytical result. However, many determinations are carried out on a daily basis and the quality control for these determinations requires the use of reference materials, although not certified but laboratory reference materials. These materials are not certified but must be homogeneous and stable with respect to the concentration of the analytes of interest and they must have a similar matrix compared to the samples to be analysed, in order to be able to perform the quality control of the analytical determinations. The reference material herein presented is an exhausted electrowinning electrolyte from a local copper producing company. The analytical determination of the metals in the solution was performed using ICP-AES with a multivariate calibration procedure. The analytes are the following : As, Ca, Cu, Fe, Na, Ni, Sb and Zn.

  4. Reference materials--a main element in a coherent reference measurement system.

    PubMed

    Dybkaer, R

    1991-04-01

    The analytical reliability of any measurement procedure requires a specifically designed, coherent reference measurement system, including interrelated measurement procedures and measurement standards such as reference materials. The latter may be characterized by three sets of characteristics. The general characteristics comprise origin, mode of production, physical state and phase, homogeneity, physical form, container, additives, storage conditions, stability, and dangerous properties. The specific characteristics describe molecular composition, analyte, purity, matrix, quantity of interest (including scale), assigned value, and uncertainty of measurement. The additional characteristics concern the way in which values for other characteristics were obtained, the hierarchical position of the material, certificate, instructions for use, and intended function. The problem areas of reference materials comprise definition of the appropriate analyte, purification, matrix, assignment of values, and nomenclature. The present ambiguous terminology is presented and a systematic structure of descriptive names is proposed (tab. 1). PMID:1868129

  5. [Study on certified reference material of iodine in kelp].

    PubMed

    Lu, Longgen; Qian, Yaling; Lu, Xiujing

    2004-09-01

    Analytical reference material of iodine in kelp was designed and prepared for accurate analysis, monitor and evaluation of iodine in trade of farming, forestry, medicine and food hygiene can be used in technical training, technical assessing, monitoring, date arbitrating and analytic method verifying for professional supervisors. This reference material was certified by neutron activation, ICP-MS, PA, GC, IC, COL method. According to Gurbb's law to judge the date of each group, it was confirmed that all of six groups certified curde date were normal distribution by checking normality D. The arithmetic mean value of all data on certified reference material of low and moderate amount was 9.3 microg/g and 85.7 microg/g respectively and, standard deviation was 0.9 microg/g and 4.9 microg/g respectively.

  6. SPOTS project and development of a standard and reference material

    NASA Astrophysics Data System (ADS)

    Burguete, R.; Patterson, E.

    2010-06-01

    The ‘Standardization Project for Optical Techniques of Strain measurement’ (SPOTS) was focused on the development of reference materials for calibrating optical systems for static strain measurement and standardized tests for evaluating the capabilities of such systems. The reference material consists of a beam in four-point bending within a monolithic frame that ensures reproducibility of the boundary and loading conditions. A procedure for the use of the reference material has been developed and leads to the evaluation of measurement uncertainties that allow the construction of confidence limits for the data obtained with the calibrated optical system. The design and methodology have been developed into a proposed draft standard which is being endorsed by VAMAS (Versailles Agreement on Materials And Standards) for review by ISO (International Standards Organisation). An overview of philosophy underpinning the proposed draft standard is presented and serves as an introduction to the reference material and standardized test and their use in providing higher confidence in optical measurements of strain.

  7. Production and characterization of a bovine liver candidate reference material

    NASA Astrophysics Data System (ADS)

    Bianchi, S. R.; Peixoto, A. M. J.; Souza, G. B.; Tullio, R. R.; Nogueira, A. R. A.

    2016-07-01

    The preparation of a bovine liver candidate reference material and the steps are taken to confirm its homogeneity, long and short term stabilities, and consensus values are described. Details of the sample preparation and the final collaborative exercise are presented. The material elemental composition was characterized by 17 elements (As, Ca, Cd, Co, Cu, Fe, K, Mg, Mo, Mn, Na, P, Pb, Se, Sr, V, and Zn) of nutritional and toxicological significance.

  8. Developing a matrix reference material for screening of transgenic rice.

    PubMed

    Li, Jun; Wu, Yuhua; Li, Xiaofei; Wang, Yulei; Zhang, Li; Li, Yunjing; Wu, Gang

    2015-12-01

    Certified reference materials (CRMs) that are compatible with detection methods are needed to detect genetically modified organisms (GMOs). Screening is the first detection step in determining the possible presence of GMO ingredients in food or feed; however, screening has been hindered by the lack of GMO CRMs. In this study, transgenic rice materials were developed via the transformation of a construct harboring 11 commonly used screening elements. Digital PCR was utilized to identify a homozygous single-copy line termed SDrice. The qualitative detections of 11 elements in 21 transgenic materials demonstrated that the genomic DNA of the SDrice was suitable for use as a positive control in the screening of GMO ingredients. The suitability of SDrice as reference material was further checked by testing the sensitivity of 11 known conventional PCR assays, ranging from 10 to 50 copies of the SDrice genome. The standard curves that were created using SDrice DNA series as calibrators all exhibited good linearities in the relationships of the Ct values with the template copy numbers in these 11 real-time PCR assays. The LODs of the real-time PCR assays were estimated to be two to five copies of the SDrice genome. Comparisons of the SDrice with other GM rice revealed that significant differences existed in both the intercepts of the standard curves and the ΔCt values of the exogenous and reference genes for the P-35S, T-nos, HPT, T-35S, and Bar assays; the SDrice was not fit for quantification of other GM rice events. This study provided a matrix reference material (RM) that was suitable for screening GM rice, determination of sensitivity and a LOD of PCR assays, and overcame some of the drawbacks of plasmid DNA as reference material. PMID:26462921

  9. Developing a matrix reference material for screening of transgenic rice.

    PubMed

    Li, Jun; Wu, Yuhua; Li, Xiaofei; Wang, Yulei; Zhang, Li; Li, Yunjing; Wu, Gang

    2015-12-01

    Certified reference materials (CRMs) that are compatible with detection methods are needed to detect genetically modified organisms (GMOs). Screening is the first detection step in determining the possible presence of GMO ingredients in food or feed; however, screening has been hindered by the lack of GMO CRMs. In this study, transgenic rice materials were developed via the transformation of a construct harboring 11 commonly used screening elements. Digital PCR was utilized to identify a homozygous single-copy line termed SDrice. The qualitative detections of 11 elements in 21 transgenic materials demonstrated that the genomic DNA of the SDrice was suitable for use as a positive control in the screening of GMO ingredients. The suitability of SDrice as reference material was further checked by testing the sensitivity of 11 known conventional PCR assays, ranging from 10 to 50 copies of the SDrice genome. The standard curves that were created using SDrice DNA series as calibrators all exhibited good linearities in the relationships of the Ct values with the template copy numbers in these 11 real-time PCR assays. The LODs of the real-time PCR assays were estimated to be two to five copies of the SDrice genome. Comparisons of the SDrice with other GM rice revealed that significant differences existed in both the intercepts of the standard curves and the ΔCt values of the exogenous and reference genes for the P-35S, T-nos, HPT, T-35S, and Bar assays; the SDrice was not fit for quantification of other GM rice events. This study provided a matrix reference material (RM) that was suitable for screening GM rice, determination of sensitivity and a LOD of PCR assays, and overcame some of the drawbacks of plasmid DNA as reference material.

  10. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (a) The procedures... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine...

  11. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (a) The procedures... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine...

  12. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (a) The procedures... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine...

  13. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (a) The procedures... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine...

  14. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (a) The procedures... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine...

  15. APEX (Air Pollution Exercise) Volume 20: Reference Materials.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Research Triangle Park, NC. Office of Manpower Development.

    The Reference Materials Manual is part of a set of 21 manuals (AA 001 009-001 029) used in APEX (Air Pollution Exercise), a computerized college and professional level "real world" game simulation of a community with urban and rural problems, industrial activities, and air pollution difficulties. For the purposes of the gaming exercise, APEX…

  16. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR 51. Any subsequent amendment to this... INDUSTRIAL EQUIPMENT Commercial Warm Air Furnaces Test Procedures § 431.75 Materials incorporated by..., “Gas-Fired Central Furnaces,” IBR approved for § 431.76. (2) Underwriters Laboratories (UL)...

  17. 10 CFR 431.133 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.133 Section 431.133 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL.... Department of Energy, Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies...

  18. 10 CFR 431.263 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.263 Section 431.263 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. (ii) U.S. Department of...

  19. 10 CFR 431.203 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.203 Section 431.203 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... of Energy, Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies Program),...

  20. 10 CFR 431.293 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.293 Section 431.293 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  1. 10 CFR 431.263 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.263 Section 431.263 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. (ii) U.S. Department of...

  2. 10 CFR 431.203 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.203 Section 431.203 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... of Energy, Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies Program),...

  3. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.223 Section 431.223 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL.... Department of Energy, Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies...

  4. 10 CFR 431.63 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.63 Section 431.63 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...

  5. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.75 Section 431.75 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND.... Department of Energy, Office of Energy Efficiency and Renewable Energy, Hearings and Dockets,...

  6. 10 CFR 431.293 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.293 Section 431.293 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  7. 10 CFR 431.63 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.63 Section 431.63 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...

  8. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.75 Section 431.75 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND.... Department of Energy, Office of Energy Efficiency and Renewable Energy, Hearings and Dockets,...

  9. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Materials incorporated by reference. 431.223 Section 431.223 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL.... Department of Energy, Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies...

  10. 40 CFR 194.13 - Submission of reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Submission of reference materials. 194.13 Section 194.13 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS CRITERIA FOR THE CERTIFICATION AND RE-CERTIFICATION OF THE WASTE ISOLATION PILOT PLANT'S COMPLIANCE WITH THE 40 CFR PART...

  11. 10 CFR 431.263 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... paragraph (b) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR... Society for Testing and Materials (ASTM) Standard F2324-03, “Standard Test Method for Prerinse Spray... to: http://www.archives.gov/federal-register/cfr/ibr-locations.html. (ii) U.S. Department of...

  12. 10 CFR 431.133 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... paragraph (b) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to this material by the standard-setting organization will not affect... Ice-Makers.” (2) American National Standards Institute (ANSI)/American Society of...

  13. 10 CFR 431.63 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.63 Section 431.63 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 51. Any subsequent...

  14. 10 CFR 431.85 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...., Washington, DC 20024, 202-586-2945, or go to: http://www1.eere.energy.gov/buildings/appliance_standards... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.85 Section 431.85 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...

  15. 10 CFR 431.85 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...., Washington, DC 20024, 202-586-2945, or go to: http://www1.eere.energy.gov/buildings/appliance_standards... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.85 Section 431.85 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...

  16. 10 CFR 431.63 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.63 Section 431.63 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 51. Any subsequent...

  17. 10 CFR 431.293 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Floor, 950 L'Enfant Plaza, SW., Washington, DC 20024, 202-586-2945, or visit http://www1.eere.energy.gov... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.293 Section 431.293 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  18. 10 CFR 431.293 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Floor, 950 L'Enfant Plaza, SW., Washington, DC 20024, 202-586-2945, or visit http://www1.eere.energy.gov... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.293 Section 431.293 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  19. 10 CFR 431.63 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Materials incorporated by reference. 431.63 Section 431.63 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 51. Any subsequent...

  20. 10 CFR 431.85 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...., Washington, DC 20024, 202-586-2945, or go to: http://www1.eere.energy.gov/buildings/appliance_standards... 10 Energy 3 2013-01-01 2013-01-01 false Materials incorporated by reference. 431.85 Section 431.85 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...

  1. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... 552(a) and 1 CFR part 51. Any subsequent amendment to this material by the standard-setting... procedures incorporated by reference. (1) Environmental Protection Agency, “ENERGY STAR Program Requirements... Agency “ENERGY STAR Program Requirements for Traffic Signals,” Version 1.1, may be obtained from...

  2. Estimation of Relative Bioavailability of Lead in Soil and Soil-Like Materials Using Young Swine

    PubMed Central

    Casteel, Stan W.; Weis, Christopher P.; Henningsen, Gerry M.; Brattin, William J.

    2006-01-01

    In this article we summarize the results of a series of studies that measured the relative bioavailability (RBA) of lead in a variety of soil and soil-like test materials. Reference material (Pb acetate) or Pb-contaminated soils were administered orally to juvenile swine twice a day for 15 days. Blood samples were collected from each animal at multiple times during the course of the study, and samples of liver, kidney, and bone were collected at sacrifice. All samples were analyzed for Pb. We estimated the RBA of a test material by fitting mathematical models to the dose–response curves for each measurement end point and finding the ratio of doses that gave equal responses. The final RBA for a test material is the simple average of the four end point–specific RBA values. Results from 19 different test materials reveal a wide range of RBA values across different exposure materials, ranging from 6 to 105%. This variability in RBA between different samples highlights the importance of reliable RBA data to help improve risk assessments for Pb in soil. Although the RBA value for a sample depends on the relative amounts of the different chemical and physical forms of Pb present, data are not yet adequate to allow reliable quantitative predictions of RBA from chemical speciation data alone. PMID:16882520

  3. EPR-based material modelling of soils

    NASA Astrophysics Data System (ADS)

    Faramarzi, Asaad; Alani, Amir M.

    2013-04-01

    In the past few decades, as a result of the rapid developments in computational software and hardware, alternative computer aided pattern recognition approaches have been introduced to modelling many engineering problems, including constitutive modelling of materials. The main idea behind pattern recognition systems is that they learn adaptively from experience and extract various discriminants, each appropriate for its purpose. In this work an approach is presented for developing material models for soils based on evolutionary polynomial regression (EPR). EPR is a recently developed hybrid data mining technique that searches for structured mathematical equations (representing the behaviour of a system) using genetic algorithm and the least squares method. Stress-strain data from triaxial tests are used to train and develop EPR-based material models for soil. The developed models are compared with some of the well-known conventional material models and it is shown that EPR-based models can provide a better prediction for the behaviour of soils. The main benefits of using EPR-based material models are that it provides a unified approach to constitutive modelling of all materials (i.e., all aspects of material behaviour can be implemented within a unified environment of an EPR model); it does not require any arbitrary choice of constitutive (mathematical) models. In EPR-based material models there are no material parameters to be identified. As the model is trained directly from experimental data therefore, EPR-based material models are the shortest route from experimental research (data) to numerical modelling. Another advantage of EPR-based constitutive model is that as more experimental data become available, the quality of the EPR prediction can be improved by learning from the additional data, and therefore, the EPR model can become more effective and robust. The developed EPR-based material models can be incorporated in finite element (FE) analysis.

  4. Overview of Uranium Isotopic Reference Materials at IRMM

    NASA Astrophysics Data System (ADS)

    Alonso-Munoz, A.; Richter, S.; Eykens, R.; Aregbe, Y.; Kuehn, H.; Verbruggen, A.

    2007-12-01

    For many applications in the geological sciences, in particular in geochemistry research, isotope ratio measurements play a significant role. For instance, in geochronology isotope abundances of uranium and its daughter products thorium and lead have been used since more than five decades to determine the age of various samples of geological interest. However, in order to validate mass spectrometric measurement procedures and to calibrate detector systems, suitable isotope reference materials are needed. IRMM is a well recognized provider for nuclear isotope reference materials to the nuclear industry and nuclear safeguards authorities, which can also be used for geological applications. This paper gives an overview of isotope reference materials for uranium prepared and certified at IRMM. These materials are synthetic isotope reference materials prepared based on proven methods of purifying and mixing highly enriched oxides. Firstly, a set of 10 mixtures of 233U, 235U and 238U was made in which the 235U/238U ratios were kept at 1:1 and the 233U/235U ratios varied from 1.0 to 10-6 (IRMM-072). This set is ideal for checking the linearity response of detectors used in isotope mass spectrometry. Recently, after the IRMM-072 series was exhausted, it has been replaced by the IRMM-073 and IRMM-074 series. Secondly the double spike IRMM-3636 with a 233U/236U ratio of 1:1 was prepared which allows internal mass fractionation correction for high precision 235U/238U ratio measurements. The 234U abundance of this double spike material is low enough to allow an accurate and precise correction of 234U/238U ratios, even for measurements of close to equilibrium uranium samples.

  5. The Metaproteome of "Park Grass" soil - a reference for EU soil science

    NASA Astrophysics Data System (ADS)

    Quinn, Gerry; Dudley, Ed; Doerr, Stefan; Matthews, Peter; Halen, Ingrid; Walley, Richard; Ashton, Rhys; Delmont, Tom; Francis, Lewis; Gazze, Salvatore Andrea; Van Keulen, Geertje

    2016-04-01

    Soil metaproteomics, the systemic extraction and identification of proteins from a soil, is key to understanding the biological and physical processes that occur within the soil at a molecular level. Until recently, direct extraction of proteins from complex soils have yielded only dozens of protein identifications due to interfering substances, such as humic acids and clay, which co-extract and/or strongly adsorb protein, often causing problems in downstream processing, e.g. mass spectrometry. Furthermore, the current most successful, direct, proteomic extraction protocol favours larger molecular weight and/or heat-stable proteins due to its extraction protocol. We have now developed a novel, faster, direct soil protein extraction protocol which also addressed the problem of interfering substances, while only requiring less than 1 gram of material per extraction. We extracted protein from the 'Genomic Observatory' Park Grass at Rothamsted Research (UK), an ideally suited geographic site as it is the longest (>150 years) continually studied experiment on ungrazed permanent grassland in the world, for which a rich history of environmental/ecological data has been collected, including high quality publically available metagenome DNA sequences. Using this improved methodology, in conjunction with the creation of high quality, curated metagenomic sequence databases, we have been able to significantly improve protein identifications from one soil due to extracting a similar number of proteins that were >90% different when compared to the best current direct protocol. This optimised metaproteomics protocol has now enabled identification of thousands of proteins from one soil, leading therefore to a deeper insight of soil system processes at the molecular scale.

  6. Dryland soil microbial communities display spatial biogeographic patterns associated with soil depth and soil parent material

    USGS Publications Warehouse

    Steven, Blaire; Gallegos-Graves, La Verne; Belnap, Jayne; Kuske, Cheryl R.

    2013-01-01

    Biological soil crusts (biocrusts) are common to drylands worldwide. We employed replicated, spatially nested sampling and 16S rRNA gene sequencing to describe the soil microbial communities in three soils derived from different parent material (sandstone, shale, and gypsum). For each soil type, two depths (biocrusts, 0–1 cm; below-crust soils, 2–5 cm) and two horizontal spatial scales (15 cm and 5 m) were sampled. In all three soils, Cyanobacteria and Proteobacteria demonstrated significantly higher relative abundance in the biocrusts, while Chloroflexi and Archaea were significantly enriched in the below-crust soils. Biomass and diversity of the communities in biocrusts or below-crust soils did not differ with soil type. However, biocrusts on gypsum soil harbored significantly larger populations of Actinobacteria and Proteobacteria and lower populations of Cyanobacteria. Numerically dominant operational taxonomic units (OTU; 97% sequence identity) in the biocrusts were conserved across the soil types, whereas two dominant OTUs in the below-crust sand and shale soils were not identified in the gypsum soil. The uniformity with which small-scale vertical community differences are maintained across larger horizontal spatial scales and soil types is a feature of dryland ecosystems that should be considered when designing management plans and determining the response of biocrusts to environmental disturbances.

  7. Lawrence Livermore National Laboratory Working Reference Material Production Pla

    SciTech Connect

    Wong, Amy; Thronas, Denise; Marshall, Robert

    1998-11-04

    This Lawrence Livermore National Laboratory (LLNL) Working Reference Material Production Plan was written for LLNL by the Los Alamos National Laboratory to address key elements of producing seven Pu-diatomaceous earth NDA Working Reference Materials (WRMS). These WRMS contain low burnup Pu ranging in mass from 0.1 grams to 68 grams. The composite Pu mass of the seven WRMS was designed to approximate the maximum TRU allowable loading of 200 grams Pu. This document serves two purposes: first, it defines all the operations required to meet the LLNL Statement of Work quality objectives, and second, it provides a record of the production and certification of the WRMS. Guidance provided in ASTM Standard Guide C1128-89 was used to ensure that this Plan addressed all the required elements for producing and certifying Working Reference Materials. The Production Plan was written to provide a general description of the processes, steps, files, quality control, and certification measures that were taken to produce the WRMS. The Plan identifies the files where detailed procedures, data, quality control, and certification documentation and forms are retained. The Production Plan is organized into three parts: a) an initial section describing the preparation and characterization of the Pu02 and diatomaceous earth materials, b) middle sections describing the loading, encapsulation, and measurement on the encapsulated WRMS, and c) final sections describing the calculations of the Pu, Am, and alpha activity for the WRMS and the uncertainties associated with these quantities.

  8. Reference Materials for Reactor Neutron Fluence Rate and Temperature Measurements

    NASA Astrophysics Data System (ADS)

    Ingelbrecht, C.

    2003-06-01

    Certified reference materials are distributed by the European Commission through the BCR® programme (over 500 CRMs) including a series of activation and fission monitor materials originally proposed by the Euratom Working Group on Reactor Dosimetry. The current range (18 CRMs) includes materials to cover the complete energy spectrum, and suitable for different irradiation times. Fission monitors are 238UO2 or 237NpO2 in the form of microspheres. Activation monitors are high purity metals (Ni, Cu, Al, Fe, Nb, Rh, or Ti), certified for interfering trace impurities, or dilute aluminium-based alloys. Reference materials newly certified are IRMM-530R A1-0.1%Au, replacing the exhausted IRMM-530 material, used as comparator for k0- standardisation, and three new Al-Co alloys (0.01, 0.1 and 1.0%Co). Others in the process of certification are A1-0.1%Ag and A1-2%Sc for thermal and epithermal fluence rate measurements and two uranium-doped glass materials intended for dosimetry by the fission-track technique. Various alloy compositions have been prepared for use as melt-wire temperature monitors with melting points ranging from 198 to 327ºC.

  9. Developing Potential New Reference Materials for Light Isotopes in Foodstuffs

    NASA Astrophysics Data System (ADS)

    Frew, Russell; Van Hale, Robert; Clarke, Dianne; Abrahim, Aiman; Resch, Christian; Mayr, Leopold; Cannavan, Andrew; Gröning, Manfred

    2013-04-01

    Measurements of subtle variations in stable isotope ratios provide the means for verifying food integrity in numerous ways. Adulterants usually have different isotopic composition so their presence in a food is readily detectable. Stable isotope measurements can also be used to determine the region of production of the food. In most cases the ability of stable isotope measurements to verify, or otherwise reject, the authenticity of the food is greatly enhanced by comparison of a result to a reference database. The more high-quality data in the database, the more statistical power is afforded by the comparison. A serious weakness at present is the lack of reference materials in food matrices available to the community. Thus researchers have to rely on in-house standards for calibration and quality assurance. The result is that there are numerous datasets published that may be internally consistent but it is exceedingly difficult to combine these datasets into a cohesive database. This is particularly important for measurements of the hydrogen isotopes. Here we present a survey of the stable isotope (^2H, ^13C and ^15N) composition of 12 Reference Materials from the International Atomic Energy Agency catalogue. All but one of these materials are plant matter and have been developed as reference materials for other applications such as radionuclide or trace element measurements. Thus they have been verified as suitable materials in terms of stability and homogeneity for those tests. The purpose of this work is to ascertain if they are similarly suitable as stable isotope reference materials. The results from our survey show that there is a wide range in elemental and isotopic composition among these materials. For example, the ^15N values range from-13.5‰ to +18.6‰ and the nitrogen elemental composition range is from 0.7% to 9.7%. The ^13C values range from -20‰ to -40‰ and the carbon elemental composition ranges from 15% to 47%. We are now in the process of

  10. Preparation and stability of milk somatic cell reference materials.

    PubMed

    Di Marzo, Larissa; Wojciechowski, Karen L; Barbano, David M

    2016-09-01

    Our objectives were to develop a method to produce milk somatic cell count (SCC) reference materials for calibration of electronic somatic cell count (ESCC) using gravity separation and to determine the effect of refrigerated storage (4°C) and freeze-thaw stability of the skim and whole milk SCC reference materials. Whole raw milk was high-temperature short-time pasteurized and split into 2 portions. One portion was gravity separated at 4°C for 22 h and the second portion was centrifugally separated to produce skim milk that was also gravity separated with somatic cells rising to the surface. After 22 h, stock solutions (low SCC skim milk, high SCC skim milk, high SCC whole milk) were prepared and preserved (bronopol). Two experiments were conducted, one to compare the shelf-life of skim and whole milk SCC standards at 4°C and one to determine the effect of freezing and thawing on SCC standards. Both experiments were replicated 3 times. Gravity separation was an effective approach to isolate and concentrate somatic cells from bovine milk and redistribute them in a skim or whole milk matrix to create a set of reference materials with a wider and more uniformly distributed range of SCC than current calibration sets. The liquid SCC reference materials stored using the common industry practice at 4°C were stable (i.e., fit for purpose, no large decrease in SCC) for a 2-wk period, whereas frozen and thawed reference materials may have a much longer useful life. A gradual decrease occurred in residual difference in ESCC (SCC × 1,000/mL) versus original assigned reference SCC over duration of refrigerated storage for both skim and whole milk SCC samples, indicating that milk ESCC of the preserved milks was gradually decreasing during 28 d of storage at 4°C by about 15,000 SCC/mL. No difference in the ESCC for skim milk was detected between refrigerated and frozen storage, whereas for whole milk the ESCC for frozen was lower than refrigerated samples. Future work is

  11. Preparation and stability of milk somatic cell reference materials.

    PubMed

    Di Marzo, Larissa; Wojciechowski, Karen L; Barbano, David M

    2016-09-01

    Our objectives were to develop a method to produce milk somatic cell count (SCC) reference materials for calibration of electronic somatic cell count (ESCC) using gravity separation and to determine the effect of refrigerated storage (4°C) and freeze-thaw stability of the skim and whole milk SCC reference materials. Whole raw milk was high-temperature short-time pasteurized and split into 2 portions. One portion was gravity separated at 4°C for 22 h and the second portion was centrifugally separated to produce skim milk that was also gravity separated with somatic cells rising to the surface. After 22 h, stock solutions (low SCC skim milk, high SCC skim milk, high SCC whole milk) were prepared and preserved (bronopol). Two experiments were conducted, one to compare the shelf-life of skim and whole milk SCC standards at 4°C and one to determine the effect of freezing and thawing on SCC standards. Both experiments were replicated 3 times. Gravity separation was an effective approach to isolate and concentrate somatic cells from bovine milk and redistribute them in a skim or whole milk matrix to create a set of reference materials with a wider and more uniformly distributed range of SCC than current calibration sets. The liquid SCC reference materials stored using the common industry practice at 4°C were stable (i.e., fit for purpose, no large decrease in SCC) for a 2-wk period, whereas frozen and thawed reference materials may have a much longer useful life. A gradual decrease occurred in residual difference in ESCC (SCC × 1,000/mL) versus original assigned reference SCC over duration of refrigerated storage for both skim and whole milk SCC samples, indicating that milk ESCC of the preserved milks was gradually decreasing during 28 d of storage at 4°C by about 15,000 SCC/mL. No difference in the ESCC for skim milk was detected between refrigerated and frozen storage, whereas for whole milk the ESCC for frozen was lower than refrigerated samples. Future work is

  12. Primary certification of reference material for electrolytic conductivity of bioethanol

    NASA Astrophysics Data System (ADS)

    da Silva, L. F.; Gomes, M. R. F.; Cassini, G. C.; Faria, A. C. V.; Fraga, I. C. S.

    2016-07-01

    Nowadays the preservation of the planet is spreading into the international scene with the use of renewable energy sources such as bioethanol. The challenge is to guarantee the quality of produced bioethanol, and the electrolytic conductivity (EC) is one of the specified parameters for this purpose. However, is necessary to demonstrate the metrological traceability of the measurement results for EC in this matrix. This study presents the certification of a reference material for EC in bioethanol by using only primary measurements. The value of primary certified reference material (CRM) is (0.77 ± 0.06) µS.cm-1, and its use will provide the metrological traceability needed for measurement results in laboratories.

  13. Homogeneity study of candidate reference material in fish matrix

    NASA Astrophysics Data System (ADS)

    Ulrich, J. C.; Sarkis, J. E. S.; Hortellani, M. A.

    2015-01-01

    A material is perfectly homogeneous with respect to a given characteristic, or composition, if there is no difference between the values obtained from one part to another. Homogeneity is usually evaluated using analysis of variance (ANOVA). However, the requirement that populations of data to be processed must have a normal distribution and equal variances greatly limits the use of this statistical tool. A more suitable test for assessing the homogeneity of RMs, known as "sufficient homogeneity", was proposed by Fearn and Thompson. In this work, we evaluate the performance of the two statistical treatments for assessing homogeneity of methylmercury (MeHg) in candidate reference material of fish tissue.

  14. Clinical Biospecimens: Reference Materials, Certified for Nominal Properties?

    PubMed Central

    2014-01-01

    This report makes the case for clinical biospecimens to be certified for nominal properties, in particular the diagnosis, and to attain the level of Reference Materials. Clinical certified biospecimens that are collected, processed, characterized, stored, and distributed by biobanks are urgently needed to facilitate diagnostic test development, evaluation, and quality assurance. Four examples are provided to illustrate this purpose and the certification approaches that could be applied are proposed. PMID:24749878

  15. 10 CFR 431.15 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... material listed for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any... §§ 431.12; 431.19; 431.20; appendix B to subpart B of part 431. (2) (c) IEC. International Electrotechnical Commission Central Office, 3, rue de Varembé, P.O. Box 131, CH-1211 GENEVA 20, Switzerland, +41...

  16. Four reference soil and rock samples for measuring element availability in the Western Energy Regions

    USGS Publications Warehouse

    Crock, J.G.; Severson, R.C.

    1980-01-01

    Attaining acceptable precision in extractable element determinations is more difficult than in total element determinations. In total element determinations, dissolution of the sample is qualitatively checked by the clarity of the solution and the absence of residues. These criteria cannot be used for extracts. Possibilities for error are introduced in virtually every step in soil extractions. Therefore, the use of reference materials whose homogeneity and element content are reasonably well known is essential for determination of extractable elements. In this report, estimates of homogeneity and element content are presented for four reference samples. Bulk samples of about 100 kilograms of each sample were ground to pass an 80-mesh sieve. The samples were homogenized and split using a Jones-type splitter. Fourteen splits of each reference sample were analyzed for total content of Ca, Co, Cu, Fe, K, Mg, Mn, Na, and Zn; DTPA-extractable Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn; exchangeable Ca, Mg, K, and Na; cation exchange capacity water-saturation-extractable Ca, Mg, K, Na, C1, and SO4; soil pH; and hot-water-extractable boron. Error measured between splits was small, indicating that the samples were homogenized adequately and that the laboratory procedure provided reproducible results.

  17. Aluminum analysis in biological reference material by nondestructive methods

    SciTech Connect

    Landsberger, S.; Arendt, A.; Keck, B.; Glascock, M.

    1988-01-01

    In recent years, the determination of aluminum in biological materials has become the subject of many research projects. This interest stems from an increasing knowledge of the toxicity of aluminum to both aquatic and human life. Unfortunately, the detection of aluminum in biological materials has proven troublesome. The use of traditional chemical determinations has been shown to be very long and somewhat complicated. Several attempts have been made using neutron activation analysis, but an interfering reaction must be taken into account. In this experiment the rabbit irradiation facilities at the University of Missouri Research Reactor were used. The aluminum concentrations for eight certified reference materials are shown. When US National Bureau of Standards (NBS) value is given as certified or as an information value, results agree very well. The results for NBS 1572 citrus leaves agree, and NBS 1577 results agree very well with that of Glascock et al.

  18. Material Spectral Emissivity Measurement Based on Two Reference Blackbodies

    NASA Astrophysics Data System (ADS)

    Cai, Jing; Yang, Yongjun; Liao, Li; Lyu, Guoyi

    2015-12-01

    Spectral emissivity is one of the important physical properties of materials. Emissivity measurement is critical for accurate temperature measurements and the evaluation of the stealth performance for materials. In this paper, a Fourier transform infrared spectrometer and an energy comparison method are used to study material emissivity measurements. Two reference blackbodies are employed for real-time measurement and correction of the spectrometer background function to enhance the emissivity measurement accuracy, to improve the design of a three-parabolic-mirror optical system, and to enlarge the optical field of view to meet the measurement requirements. The linearity of the system is measured using a mercury cadmium telluride detector and a deuterated triglycine sulfate detector. The results indicate that the linear range of the system meets the emissivity measurement requirements for the temperature range from 50°C to 1000° C. The effective radiation surface is introduced as a parameter of the reference blackbodies to reduce the influence of the measurement distance. The Fourier transform infrared spectrometer is used to measure the spectral emissivity of a conductive silica film and SiC, respectively, at different temperatures in the wavelength range of 1 \\upmu m to 25 \\upmu m. The expanded uncertainty is less than 5 %.

  19. Characterization of Ricin and R. communis Agglutinin Reference Materials.

    PubMed

    Worbs, Sylvia; Skiba, Martin; Söderström, Martin; Rapinoja, Marja-Leena; Zeleny, Reinhard; Russmann, Heiko; Schimmel, Heinz; Vanninen, Paula; Fredriksson, Sten-Åke; Dorner, Brigitte G

    2015-11-26

    Ricinus communis intoxications have been known for centuries and were attributed to the toxic protein ricin. Due to its toxicity, availability, ease of preparation, and the lack of medical countermeasures, ricin attracted interest as a potential biological warfare agent. While different technologies for ricin analysis have been established, hardly any universally agreed-upon "gold standards" are available. Expert laboratories currently use differently purified in-house materials, making any comparison of accuracy and sensitivity of different methods nearly impossible. Technically challenging is the discrimination of ricin from R. communis agglutinin (RCA120), a less toxic but highly homologous protein also contained in R. communis. Here, we established both highly pure ricin and RCA120 reference materials which were extensively characterized by gel electrophoresis, liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI MS/MS), and matrix-assisted laser desorption ionization-time of flight approaches as well as immunological and functional techniques. Purity reached >97% for ricin and >99% for RCA120. Different isoforms of ricin and RCA120 were identified unambiguously and distinguished by LC-ESI MS/MS. In terms of function, a real-time cytotoxicity assay showed that ricin is approximately 300-fold more toxic than RCA120. The highly pure ricin and RCA120 reference materials were used to conduct an international proficiency test.

  20. Characterization of Ricin and R. communis Agglutinin Reference Materials.

    PubMed

    Worbs, Sylvia; Skiba, Martin; Söderström, Martin; Rapinoja, Marja-Leena; Zeleny, Reinhard; Russmann, Heiko; Schimmel, Heinz; Vanninen, Paula; Fredriksson, Sten-Åke; Dorner, Brigitte G

    2015-12-01

    Ricinus communis intoxications have been known for centuries and were attributed to the toxic protein ricin. Due to its toxicity, availability, ease of preparation, and the lack of medical countermeasures, ricin attracted interest as a potential biological warfare agent. While different technologies for ricin analysis have been established, hardly any universally agreed-upon "gold standards" are available. Expert laboratories currently use differently purified in-house materials, making any comparison of accuracy and sensitivity of different methods nearly impossible. Technically challenging is the discrimination of ricin from R. communis agglutinin (RCA120), a less toxic but highly homologous protein also contained in R. communis. Here, we established both highly pure ricin and RCA120 reference materials which were extensively characterized by gel electrophoresis, liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI MS/MS), and matrix-assisted laser desorption ionization-time of flight approaches as well as immunological and functional techniques. Purity reached >97% for ricin and >99% for RCA120. Different isoforms of ricin and RCA120 were identified unambiguously and distinguished by LC-ESI MS/MS. In terms of function, a real-time cytotoxicity assay showed that ricin is approximately 300-fold more toxic than RCA120. The highly pure ricin and RCA120 reference materials were used to conduct an international proficiency test. PMID:26703723

  1. Characterization of Ricin and R. communis Agglutinin Reference Materials

    PubMed Central

    Worbs, Sylvia; Skiba, Martin; Söderström, Martin; Rapinoja, Marja-Leena; Zeleny, Reinhard; Russmann, Heiko; Schimmel, Heinz; Vanninen, Paula; Fredriksson, Sten-Åke; Dorner, Brigitte G.

    2015-01-01

    Ricinus communis intoxications have been known for centuries and were attributed to the toxic protein ricin. Due to its toxicity, availability, ease of preparation, and the lack of medical countermeasures, ricin attracted interest as a potential biological warfare agent. While different technologies for ricin analysis have been established, hardly any universally agreed-upon “gold standards” are available. Expert laboratories currently use differently purified in-house materials, making any comparison of accuracy and sensitivity of different methods nearly impossible. Technically challenging is the discrimination of ricin from R. communis agglutinin (RCA120), a less toxic but highly homologous protein also contained in R. communis. Here, we established both highly pure ricin and RCA120 reference materials which were extensively characterized by gel electrophoresis, liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI MS/MS), and matrix-assisted laser desorption ionization–time of flight approaches as well as immunological and functional techniques. Purity reached >97% for ricin and >99% for RCA120. Different isoforms of ricin and RCA120 were identified unambiguously and distinguished by LC-ESI MS/MS. In terms of function, a real-time cytotoxicity assay showed that ricin is approximately 300-fold more toxic than RCA120. The highly pure ricin and RCA120 reference materials were used to conduct an international proficiency test. PMID:26703723

  2. Molecularly uniform poly(ethylene glycol) certified reference material

    NASA Astrophysics Data System (ADS)

    Takahashi, Kayori; Matsuyama, Shigetomo; Kinugasa, Shinichi; Ehara, Kensei; Sakurai, Hiromu; Horikawa, Yoshiteru; Kitazawa, Hideaki; Bounoshita, Masao

    2015-02-01

    A certified reference material (CRM) for poly(ethylene glycol) with no distribution in the degree of polymerization was developed. The degree of polymerization of the CRM was accurately determined to be 23. Supercritical fluid chromatography (SFC) was used to separate the molecularly uniform polymer from a standard commercial sample with wide polydispersity in its degree of polymerization. Through the use of a specific fractionation system coupled with SFC, we are able to obtain samples of poly(ethylene glycol) oligomer with exact degrees of polymerization, as required for a CRM produced by the National Metrology Institute of Japan.

  3. Copper Oxide Precipitates in NBS Standard Reference Material 482

    PubMed Central

    Windsor, Eric S.; Carlton, Robert A.; Gillen, Greg; Wight, Scott A.; Bright, David S.

    2002-01-01

    Copper oxide has been detected in the copper containing alloys of NBS Standard Reference Material (SRM) 482. This occurrence is significant because it represents heterogeneity within a standard reference material that was certified to be homogeneous on a micrometer scale. Oxide occurs as elliptically to spherically shaped precipitates whose size differs with alloy composition. The largest precipitates occur in the Au20-Cu80 alloy and range in size from submicrometer up to 2 μm in diameter. Precipitates are observed using light microscopy, electron microscopy, and secondary ion mass spectrometry (SIMS). SIMS has demonstrated that the precipitates are present within all the SRM 482 wires that contain copper. Only the pure gold wire is precipitate free. Initial results from the analysis of the Au20-Cu80 alloy indicate that the percentage of precipitates is less than 1 % by area. Electron probe microanalysis (EPMA) of large (2 μm) precipitates in this same alloy indicates that precipitates are detectable by EPMA and that their composition differs significantly from the certified alloy composition. The small size and low percentage of these oxide precipitates minimizes the impact that they have upon the intended use of this standard for electron probe microanalysis. Heterogeneity caused by these oxide precipitates may however preclude the use of this standard for automated EPMA analyses and other microanalysis techniques. PMID:27446759

  4. Lithium isotope composition of basalt glass reference material.

    PubMed

    Kasemann, Simone A; Jeffcoate, Alistair B; Elliott, Tim

    2005-08-15

    We present data on the lithium isotope compositions of glass reference materials from the United States Geological Survey (USGS) and the National Institute of Standards and Technology (NIST) determined by multicollector inductively coupled plasma mass spectrometry (MC-ICPMS), thermal ionization mass spectrometry (TIMS), and secondary ionization mass spectrometry (SIMS). Our data on the USGS basaltic glass standards agree within 2 per thousand, independent of the sample matrix or Li concentration. For SIMS analysis, we propose use of the USGS glasses GSD-1G (delta(7)Li 31.14 +/- 0.8 per thousand, 2sigma) and BCR-2G (delta(7)Li 4.08 +/- 1.0 per thousand, 2sigma) as suitable standards that cover a wide range of Li isotope compositions. Lithium isotope measurements on the silica-rich NIST 600 glass series by MC-ICPMS and TIMS agree within 0.8 per thousand, but SIMS analyses show systematic isotopic differences. Our results suggest that SIMS Li isotope analyses have a significant matrix bias in high-silica materials. Our data are intended to serve as a reference for both microanalytical and bulk analytical techniques and to improve comparisons between Li isotope data produced by different methodologies.

  5. Purity Determination of Acetaldehyde in an Acetaldehyde Certified Reference Material.

    PubMed

    Yamazaki, Taichi; Watanabe, Takuro; Nakamura, Satoe; Kato, Kenji

    2015-01-01

    Acetaldehyde is regulated as a toxic substance in various fields, and the method for monitoring or analysis of acetaldehyde is important. However, handling is difficult because of the high reactivity and low boiling point of acetaldehyde. Therefore, a reference material for high purity acetaldehyde with high accuracy was not available. Although the measuring method of acetaldehyde as a reagent is published in the Japanese Industrial Standard (JIS) where the specification of acetaldehyde purity is more than 80%, the analytical method described in JIS is not enough for an accuracy purity determination method. In this research, the high precision purity determination method for development of a certified reference material (CRM) of acetaldehyde was examined. By controlling the volatility and reactivity of acetaldehyde, we established the purity determination method of acetaldehyde with a relative standard uncertainty of less than 0.3%. Furthermore, this method was applied to develop a high purity acetaldehyde CRM with an expanded uncertainty of 0.005 kg kg(-1) (k = 2). PMID:26063006

  6. The new IAEA reference material: IAEA-434 technologically enhanced naturally occurring radioactive materials (TENORM) in phosphogypsum.

    PubMed

    Shakhashiro, A; Sansone, U; Wershofen, H; Bollhöfer, A; Kim, C K; Kim, C S; Kis-Benedek, G; Korun, M; Moune, M; Lee, S H; Tarjan, S; Al-Masri, M S

    2011-01-01

    A reliable determination of Technologically Enhanced Naturally Occurring Radioactive Materials in phosphogypsum is necessary to comply with radiation protection and environmental regulations. In this respect, a new phosphogypsum reference material was produced and certified to assist in the validation of analytical methods and the quality assurance of produced analytical results. This paper presents the sample preparation methodology, material homogeneity assessment, characterization campaign results and assignment of property values, and associated uncertainties. The reference values and associated uncertainties for Pb-210, Ra-226, Th-230, U-234 and U-238 were established based on consensus values calculated from analytical results reported by three National Metrology Institutes and five expert laboratories.

  7. Development and characterisation of a new line width reference material

    NASA Astrophysics Data System (ADS)

    Dai, Gaoliang; Zhu, Fan; Heidelmann, Markus; Fritz, Georg; Bayer, Thomas; Kalt, Samuel; Fluegge, Jens

    2015-11-01

    A new critical dimension (CD, often synonymously used for line width) reference material with improved vertical parallel sidewalls (IVPSs) has been developed and characterised. The sample has a size of 6 mm  ×  6 mm, consisting of 4 groups of 5  ×  5 feature patterns. Each feature pattern has a group of five reference line features with a nominal CD of 50 nm, 70 nm, 90 nm, 110 nm and 130 nm, respectively. Each feature pattern includes a pair of triangular alignment marks, applicable for precisely identifying the target measurement position, e.g. for comparison or calibration between different tools. The geometry of line features has been investigated thoroughly using a high-resolution transmission electron microscope and a CD atomic force microscope (CD-AFM). Their results indicate the high quality of the line features: the top corner radius of  <7 nm, vertical sidewall (slope mostly within 90°  ±  0.5°) and very small line width variation (LWR down to 0.36 nm). The application of the developed sample for calibrating the scaling factor and effective tip geometry of the CD-AFM are demonstrated. The scaling factor of the CD-AFM is calibrated to be 0.9988, coinciding well with the theoretical value 1 as the tool was calibrated to a traceable metrological atomic force microscope. The effective width of a CDR120-EBD tip is calibrated as 128.32 nm. Finally, a strategy for the non-destructive calibration of the developed sample is introduced, which enables the application of the reference material in practice.

  8. Evaluation of New Geological Reference Materials for U-Series Measurements

    NASA Astrophysics Data System (ADS)

    Denton, J. S.; Goldstein, S. J.; Nunn, A. J.; Ui Chearnaigh, K.; Amato, R.; Murrell, M. T.

    2012-12-01

    Uranium-series analytical measurements are widely used in geochemistry, geochronology, paleoclimatology, volcanology, environmental risk assessment and other fields. Recent advances in high-resolution, rapid, in situ microanalytical techniques e.g. LA-ICP-MS and SIMS present numerous opportunities for the geoanalytical community. As with other analytical techniques, the quality of the elemental concentration and isotopic data obtained through microanalytical techniques is dependent on the accurate characterization of suitable reference materials. Even for the case of fs-laser ablation applications, a range of well-characterized standards are required for high precision U-series work. Advances have been made in evaluating existing standard reference materials for U-series isotopic analysis, but this work is ongoing as more reference materials become available. In this study we present MC-TIMS and MC-ICP-MS results for uranium and thorium isotopic ratios and elemental concentrations measured in a suite of newly available Chinese Geological Standard Glasses (CGSG) designed for microanalysis. These glasses exhibit a range of chemical compositions including basalt, syenite, andesite and a soil. U concentrations for these glasses range from ≈2 to 14 μg/g and [Th]/[U] ratios range from ≈4 to 6. Uranium and thorium concentration and isotopic data will also be presented for rhyolitic obsidian from Macusani, SE Peru, which can be used as a rhyolitic reference material. These high-precision and high-accuracy ratios, from a suite of standards that exhibit a range of natural, non-basaltic compositions, will complement data from existing standards and expand the catalogue of reference materials that are appropriate for in situ U-series work. These results can be used to assess the performance of microanalytical techniques and will facilitate inter-laboratory comparison of data within the broader geoscience community.

  9. Flouescence reference materials used for optical and biophotonic applications

    NASA Astrophysics Data System (ADS)

    Engel, A.; Otterman, C.; Klahn, J.; Enseling, D.; Korb, T.; Resch-Genger, U.; Hoffmann, K.; Schweizer, S.; Selling, J.; Kynast, U.; Koberling, F.; Rupertus, V.

    2007-07-01

    Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools and detection methods for product and process control, material sciences, environmental and bio-technical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. According to DIN/ISO 17025 certified standards are used for fluorescence diagnostics having the drawback of giving relative values for fluorescence intensities only. Therefore reference materials for a quantitative characterization have to be related directly to the materials under investigation. In order to evaluate these figures it is necessary to calculate absolute numbers like absorption/excitation cross sections and quantum yield. This can be done for different types of dopands in different materials like glass, glass ceramics, crystals or nano crystalline material embedded in polymer matrices. Based on the optical spectroscopy data we will discuss options for characteristic doped glasses and glass ceramics with respect to scattering and absorption regime. It has shown recently for YAG:Ce glass ceramics that for a proper determination of the quantum efficiency in these highly scattering media a reference material with similar scattering and fluorescent properties is required. This may be performed using the emission decay measurement diagnostics, where the decay time is below 100 ns. In this paper we present first results of these aspects using well performing LUMOGEN RED organic pigments for a comparison of mainly transparent glass with glass ceramics doped with various amounts of dopands e.g. ions of raw earth elements and transition metals. The LUMOGEN red is embedded in silica and polyurethane matrices. Characterisations on wavelength accuracy and lifetime for different environmental conditions (temperature, UV irradiation) have been performed. Moreover intensity patterns and results for homogeneity, isotropy, photo and thermal stability will be discussed. In a next

  10. The low-level radioactivity ocean sediment standard reference material

    SciTech Connect

    Inn, K.G.W.; Lin, Z.; Liggett, W.S.; Krey, P.W.

    1995-12-31

    Over the past decades, on the order of 10{sup 15} Becquerel nuclear waste have been stored in the oceans. Potential contamination of the oceans from leaking nuclear waste has caused world wide concern. Currently, early warning of ocean contamination near the waste dumping sites rely on monitoring systems being set up by different countries and agencies. Because the determination of low-level radioactivity in ocean sediment is a difficult technical task, a basis for measurement quality assurance, methods verification, and data comparability is needed. The recently certified NIST ocean sediment Standard Reference Material (SRM-4355) is a composite of 1% contaminated Irish Sea sediment and 99% of Chesapeake Bay sediment by weight. The sediments were blended, pulverized to a median particle size of 8 {mu}m, and reblended to achieve acceptable sample homogeneity. A statistical assessment of the intercomparison results from 19 laboratories has shown the material to be homogeneous down to 10 grams. The certified radionuclide concentration range from 0.4 to 230 mBq/g. A variety of radiochemical procedures and detection techniques have been used in the measurements to minimize possible systematic bias. Twelve radionuclides including {sup 40}K, {sup 90}Sr, {sup 137}Cs, {sup 226}Ra, {sup 228}Th, {sup 230}Th, {sup 232}Th, {sup 234}U, {sup 235}U, {sup 238}U, {sup 238}Pu, and {sup (239+240)}Pu were certified. The mean values were reported for an additional 10 uncertified radionuclides: {sup 129}I, {sup 155}Eu, {sup 210}Po, {sup 210}Pb, {sup 212}Pb, {sup 214}Pb, {sup 214}Bi, {sup 228}Ra, {sup 237}Np, and {sup 241}Am. The standard reference material in unit quantities of about 100 gram each will be available by the end of 1995.

  11. Characterization of Three Berry Standard Reference Materials for Nutrients

    PubMed Central

    Wood, Laura J.; Sharpless, Katherine E.; Pichon, Monique; Porter, Barbara J.; Yen, James H.; Ehling, Stefan

    2011-01-01

    The National Institute of Standards and Technology (NIST) has been working with the National Institutes of Health Office of Dietary Supplements to produce Standard Reference Materials (SRMs) of interest to analysts of dietary supplements. Some of these SRMs are traditional foods including SRM 3281 Cranberry (Fruit), SRM 3282 Low-Calorie Cranberry Juice Cocktail, and SRM 3287 Blueberry (Fruit), which have been characterized for nine nutritional elements and sugars. The blueberries have also been characterized for proximates, two water-soluble vitamins, and amino acids. These new materials are intended for use in method development and validation as well as for quality assurance and traceability when assigning values to in-house control materials. Foods can be difficult to analyze because of matrix effects. With the addition of these three new SRMs, it is now possible to more closely match controls to matrices and analyte levels for fruit and vegetable test samples. Several nutritional elements in these three SRMs are present at lower levels than those in other food-matrix SRMs. PMID:21688777

  12. Bias detection and certified reference materials for random measurands

    NASA Astrophysics Data System (ADS)

    Rukhin, Andrew L.

    2015-12-01

    A problem that frequently occurs in metrology is the bias checking of data obtained by a laboratory against the specified value and uncertainty estimate given in the certificate of analysis. The measurand—a property of a certified reference material (CRM)—is supposed to be random with a normal distribution whose parameters are given by the certificate specifications. The laboratory’s data from subsequent measurements of the CRM (a CRM experiment) are summarized by the sample mean value and its uncertainty which is commonly based on a repeatability standard deviation. New confidence intervals for the lab’s bias are derived. Although they may lack intuitive appeal, those obtained by using higher order asymptotic methods, compared and contrasted in this paper, are recommended.

  13. Scalar material reference systems and loop quantum gravity

    NASA Astrophysics Data System (ADS)

    Giesel, K.; Thiemann, T.

    2015-07-01

    In the past, the possibility to employ (scalar) material reference systems in order to describe classical and quantum gravity directly in terms of gauge invariant (Dirac) observables has been emphasized frequently. This idea has been picked up more recently in loop quantum gravity with the aim to perform a reduced phase space quantization of the theory, thus possibly avoiding problems with the (Dirac) operator constraint quantization method for a constrained system. In this work, we review the models that have been studied on the classical and/or the quantum level and parametrize the space of theories considered so far. We then describe the quantum theory of a model that, to the best of our knowledge, has only been considered classically so far. This model could arguably be called the optimal one in this class of models considered as it displays the simplest possible true Hamiltonian, while at the same time reducing all constraints of general relativity.

  14. Certification of a new certified reference material of honokiol.

    PubMed

    Yang, Shiying; Yang, Dezhi; Hu, Kun; Zhou, Haohui; Guo, Yonghui; Du, Guanhua; Lu, Yang

    2015-07-01

    Honokiol is the most important active pharmaceutical ingredient in Magnolia officinalis, which is a famous traditional Chinese medicine and commonly used in clinical practice. In order to control the quality of honokiol and related pharmaceuticals, a new certified reference material (CRM) of honokiol was developed. The studies of sample preparation, homogeneity, stability, value assignment, and uncertainty evaluation were accomplished in this paper. Three different methods, including differential scanning calorimetry (DSC), mass balance method (MB), and coulometric titration (CT), were employed to determine the purity of honokiol. Specifically, the DSC and CT methods for purity determination of honokiol were established for the first time. The purity of honokiol CRM, after validation and evaluation, was found to be 99.3%, with an expanded uncertainty of 0.5% (k = 2).

  15. New Carbonate Standard Reference Materials for Boron Isotope Geochemistry

    NASA Astrophysics Data System (ADS)

    Stewart, J.; Christopher, S. J.; Day, R. D.

    2015-12-01

    The isotopic composition of boron (δ11B) in marine carbonates is well established as a proxy for past ocean pH. Yet, before palaeoceanographic interpretation can be made, rigorous assessment of analytical uncertainty of δ11B data is required; particularly in light of recent interlaboratory comparison studies that reported significant measurement disagreement between laboratories [1]. Well characterised boron standard reference materials (SRMs) in a carbonate matrix are needed to assess the accuracy and precision of carbonate δ11B measurements throughout the entire procedural chemistry; from sample cleaning, to ionic separation of boron from the carbonate matrix, and final δ11B measurement by multi-collector inductively coupled plasma mass spectrometry. To date only two carbonate reference materials exist that have been value-assigned by the boron isotope measurement community [2]; JCp-1 (porites coral) and JCt-1 (Giant Clam) [3]. The National Institute of Standards and Technology (NIST) will supplement these existing standards with new solution based inorganic carbonate boron SRMs that replicate typical foraminiferal and coral B/Ca ratios and δ11B values. These new SRMs will not only ensure quality control of full procedural chemistry between laboratories, but have the added benefits of being both in abundant supply and free from any restrictions associated with shipment of biogenic samples derived from protected species. Here we present in-house δ11B measurements of these new boron carbonate SRM solutions. These preliminary data will feed into an interlaboratory comparison study to establish certified values for these new NIST SRMs. 1. Foster, G.L., et al., Chemical Geology, 2013. 358(0): p. 1-14. 2. Gutjahr, M., et al., Boron Isotope Intercomparison Project (BIIP): Development of a new carbonate standard for stable isotopic analyses. Geophysical Research Abstracts, EGU General Assembly 2014, 2014. 16(EGU2014-5028-1). 3. Inoue, M., et al., Geostandards and

  16. Production of Working Reference Materials for the Capability Evaluation Project

    SciTech Connect

    Phillip D. Noll, Jr.; Robert S. Marshall

    1999-03-01

    Nondestructive waste assay (NDA) methods are employed to determine the mass and activity of waste-entrained radionuclides as part of the National TRU (Trans-Uranic) Waste Characterization Program. In support of this program the Idaho National Engineering and Environmental Laboratory Mixed Waste Focus Area developed a plan to acquire capability/performance data on systems proposed for NDA purposes. The Capability Evaluation Project (CEP) was designed to evaluate the NDA systems of commercial contractors by subjecting all participants to identical tests involving 55 gallon drum surrogates containing known quantities and distributions of radioactive materials in the form of sealed-source standards, referred to as working reference materials (WRMs). Although numerous Pu WRMs already exist, the CEP WRM set allows for the evaluation of the capability and performance of systems with respect to waste types/configurations which contain increased amounts of {sup 241}Am relative to weapons grade Pu, waste that is dominantly {sup 241}Am, as well as wastes containing various proportions of depleted uranium. The CEP WRMs consist of a special mixture of PuO{sub 2}/AmO{sub 2} (IAP) and diatomaceous earth (DE) or depleted uranium (DU) oxide and DE and were fabricated at Los Alamos National Laboratory. The IAP WRMS are contained inside a pair of welded inner and outer stainless steel containers. The DU WRMs are singly contained within a stainless steel container equivalent to the outer container of the IAP standards. This report gives a general overview and discussion relating to the production and certification of the CEP WRMs.

  17. Trace element distribution and mobilization in Scottish soils with particular reference to cobalt, copper and molybdenum.

    PubMed

    Berrow, M L; Ure, A M

    1986-03-01

    Total and extractable trace element contents have been determined in about 1000 soil profiles representing the main soil series occurring throughout Scotland. The frequency distributions of a number of trace elements in these soils are described and some relationships between total and extractable contents discussed. The geological nature of the soil parent material, soil texture, organic matter content and environmental contamination are the principal factors controlling soil total contents. Soil drainage class, because of its effect on mineral weathering and soil oxidation-reduction conditions, has a major influence on soil extractable contents, availability to plants and crop uptake. Particular attention is paid to cobalt, copper and molybdenum because of their importance for animal health in Scotland.

  18. Anorganic fluorescence reference materials for decay time of fluorescence emission

    NASA Astrophysics Data System (ADS)

    Engel, A.; Ottermann, C.; Klahn, J.; Korb, T.; Resch-Genger, U.; Hoffmann, K.; Kynast, U.; Rupertus, V.

    2008-02-01

    Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools, detection methods and imaging applications for product and process control, material sciences, environmental and bio-technical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. According to DIN/ISO 17025 certified standards are used for steady state fluorescence diagnostics, a method having the drawback of giving relative values for fluorescence intensities only. Therefore reference materials for a quantitative characterization have to be related directly to the materials under investigation. In order to evaluate these figures it is necessary to calculate absolute numbers such as absorption/excitation cross sections and quantum yield. This has been done for different types of dopands in different materials such as glass, glass ceramics, crystals or nano crystalline material embedded in polymer matrices. Samples doped with several fluophores of different emission wavelengths and decay times are required for fluorescent multiplexing applications. Decay times shorter than 100 ns are of special interest. In addition, a proper knowledge is necessary of quantum efficiency in highly scattering media. Recently, quantum efficiency in YAG:Ce glass ceramics has been successfully investigated. Glass and glass ceramics doped with threefold charged rare earth elements are available. However, these samples have the disadvantage of emission decay times much longer than 1 microsecond, due to the excitation and emission of their optical forbidden electronic transitions. Therefore first attempts have been made to produce decay-time standards based on organic and inorganic fluophores. Stable LUMOGEN RED pigments and YAG:Ce phosphors are diluted simultaneously in silicone matrices using a wide range of concentrations between 0.0001 and 2 wt%. Organic LUMOGEN RED has decay times in the lower nanosecond range with a slight dependency on concentration

  19. Long-term monitoring of soil gas radon and permeability at two reference sites.

    PubMed

    Chen, Jing; Falcomer, Renato; Ly, Jim; Wierdsma, Jessica; Bergman, Lauren

    2008-01-01

    The long-term monitoring of soil radon variations was conducted at two reference sites in Ottawa. The purpose of this study was to determine whether a single soil radon survey could provide a representative soil radon characteristic of the site. Results showed that during the normal field survey period from June to September in Canada, a single field survey with multiple measurements of soil gas radon concentrations at a depth of 80 cm can characterise the soil radon level of a site within a deviation of +/-30%. Direct in situ soil permeability measurements exhibited, however, large variations even within an area of only 10 x 10 m(2). Considering such large variations and the weight of the equipment, soil permeability can be determined by direct measurements whenever possible or by other qualitative evaluation methods for sites that are hard to access with heavy equipment.

  20. Science Reference Materials for Children and Young Adults

    ERIC Educational Resources Information Center

    Strickler, Richard L.

    1974-01-01

    After a brief discussion of science reference service, there is a list of science reference books. First are general science books, then specific lists by broad Dewey decimal classes. Grade levels are given for each work. (LS)

  1. Laboratory Reference Spectroscopy of Icy Satellite Candidate Surface Materials (Invited)

    NASA Astrophysics Data System (ADS)

    Dalton, J. B.; Jamieson, C. S.; Shirley, J. H.; Pitman, K. M.; Kariya, M.; Crandall, P.

    2013-12-01

    The bulk of our knowledge of icy satellite composition continues to be derived from ultraviolet, visible and infrared remote sensing observations. Interpretation of remote sensing observations relies on availability of laboratory reference spectra of candidate surface materials. These are compared directly to observations, or incorporated into models to generate synthetic spectra representing mixtures of the candidate materials. Spectral measurements for the study of icy satellites must be taken under appropriate conditions (cf. Dalton, 2010; also http://mos.seti.org/icyworldspectra.html for a database of compounds) of temperature (typically 50 to 150 K), pressure (from 10-9 to 10-3 Torr), viewing geometry, (i.e., reflectance), and optical depth (must manifest near infrared bands but avoid saturation in the mid-infrared fundamentals). The Planetary Ice Characterization Laboratory (PICL) is being developed at JPL to provide robust reference spectra for icy satellite surface materials. These include sulfate hydrates, hydrated and hydroxylated minerals, and both organic and inorganic volatile ices. Spectral measurements are performed using an Analytical Spectral Devices FR3 portable grating spectrometer from .35 to 2.5 microns, and a Thermo-Nicolet 6500 Fourier-Transform InfraRed (FTIR) spectrometer from 1.25 to 20 microns. These are interfaced with the Basic Extraterrestrial Environment Simulation Testbed (BEEST), a vacuum chamber capable of pressures below 10-9 Torr with a closed loop liquid helium cryostat with custom heating element capable of temperatures from 30-800 Kelvins. To generate optical constants (real and imaginary index of refraction) for use in nonlinear mixing models (i.e., Hapke, 1981 and Shkuratov, 1999), samples are ground and sieved to six different size fractions or deposited at varying rates to provide a range of grain sizes for optical constants calculations based on subtractive Kramers-Kronig combined with Hapke forward modeling (Dalton and

  2. LA-ICP-MS of magnetite: Methods and reference materials

    USGS Publications Warehouse

    Nadoll, P.; Koenig, A.E.

    2011-01-01

    Magnetite (Fe3O4) is a common accessory mineral in many geologic settings. Its variable geochemistry makes it a powerful petrogenetic indicator. Electron microprobe (EMPA) analyses are commonly used to examine major and minor element contents in magnetite. Laser ablation ICP-MS (LA-ICP-MS) is applicable to trace element analyses of magnetite but has not been widely employed to examine compositional variations. We tested the applicability of the NIST SRM 610, the USGS GSE-1G, and the NIST SRM 2782 reference materials (RMs) as external standards and developed a reliable method for LA-ICP-MS analysis of magnetite. LA-ICP-MS analyses were carried out on well characterized magnetite samples with a 193 nm, Excimer, ArF LA system. Although matrix-matched RMs are sometimes important for calibration and normalization of LA-ICP-MS data, we demonstrate that glass RMs can produce accurate results for LA-ICP-MS analyses of magnetite. Cross-comparison between the NIST SRM 610 and USGS GSE-1G indicates good agreement for magnetite minor and trace element data calibrated with either of these RMs. Many elements show a sufficiently good match between the LA-ICP-MS and the EMPA data; for example, Ti and V show a close to linear relationship with correlation coefficients, R2 of 0.79 and 0.85 respectively. ?? 2011 The Royal Society of Chemistry.

  3. Development of working reference materials for clinical virology.

    PubMed

    Fryer, Jacqueline F; Baylis, Sally A; Gottlieb, Anna L; Ferguson, Morag; Vincini, Giuseppe A; Bevan, Valerie M; Carman, William F; Minor, Philip D

    2008-12-01

    Nucleic acid amplification technique (NAT)-based assays are replacing traditional diagnostic methods in clinical laboratories. However, many of these assays are developed in-house and the lack of standardised reference materials has hindered assay implementation and control. Consequently, in the UK, the Clinical Virology Network (CVN), the National Institute for Biological Standards and Control (NIBSC), and the Health Protection Agency (HPA), are working in collaboration to develop working standards or 'run controls' for diagnostic NAT-based assays, particularly real-time PCR. These run controls are intended for use in microbiology laboratories and are designed to be extracted and amplified in the same way as clinical samples and included in each assay run. The aim is to enable clinical laboratories to continuously monitor the performance of their diagnostic NAT assays on a run-by-run basis allowing inter-laboratory comparisons, and ultimately improving the consistency of results. At present, eight candidate run controls representing clinically relevant viral targets have been prepared for evaluation by CVN laboratories. Data have been returned on the performance of each run control in routine diagnostic assays. Preliminary results presented here indicate a high level of variability in intra- and inter-assay detection of these targets, highlighting the need for standardisation of assays within molecular diagnostics.

  4. Standard Reference Material (SRM 1990) For Single Crystal Diffractometer Alignment

    PubMed Central

    Wong-Ng, W.; Siegrist, T.; DeTitta, G. T.; Finger, L. W.; Evans, H. T.; Gabe, E. J.; Enright, G. D.; Armstrong, J. T.; Levenson, M.; Cook, L. P.; Hubbard, C. R.

    2001-01-01

    An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and (2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material® for single crystal diffractometer alignment. This SRM is a set of ≈3500 units of Cr-doped Al2O3, or ruby spheres [(0.420.011 mole fraction % Cr (expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals: the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a=4.7608 ű0.0062 Å, and c=12.9979 ű0.020 Å (95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at (Bell Laboratories) Lucent Technologies and at NRC of Canada (39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Hägg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies– are rhombohedral, with space group R3¯c. The certified mean unit cell parameters are a=4.76080±0.00029 Å, and c=12.99568 ű0.00087 Å (expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Hägg transmission measurements on five samples of powdered rubies (a=4.7610 ű0.0013 Å, and c = 12

  5. Standard Reference Material (SRM 1990) For Single Crystal Diffractometer Alignment.

    PubMed

    Wong-Ng, W; Siegrist, T; DeTitta, G T; Finger, L W; Evans, H T; Gabe, E J; Enright, G D; Armstrong, J T; Levenson, M; Cook, L P; Hubbard, C R

    2001-01-01

    An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and (2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material(®) for single crystal diffractometer alignment. This SRM is a set of ≈3500 units of Cr-doped Al2O3, or ruby spheres [(0.420.011 mole fraction % Cr (expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals: the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a=4.7608 ű0.0062 Å, and c=12.9979 ű0.020 Å (95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at (Bell Laboratories) Lucent Technologies and at NRC of Canada (39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Hägg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies- are rhombohedral, with space group [Formula: see text]. The certified mean unit cell parameters are a=4.76080±0.00029 Å, and c=12.99568 ű0.00087 Å (expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Hägg transmission measurements on five samples of powdered rubies (a=4.7610 ű0.0013

  6. Standard Reference Material (SRM 1990) For Single Crystal Diffractometer Alignment.

    PubMed

    Wong-Ng, W; Siegrist, T; DeTitta, G T; Finger, L W; Evans, H T; Gabe, E J; Enright, G D; Armstrong, J T; Levenson, M; Cook, L P; Hubbard, C R

    2001-01-01

    An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and (2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material(®) for single crystal diffractometer alignment. This SRM is a set of ≈3500 units of Cr-doped Al2O3, or ruby spheres [(0.420.011 mole fraction % Cr (expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals: the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a=4.7608 ű0.0062 Å, and c=12.9979 ű0.020 Å (95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at (Bell Laboratories) Lucent Technologies and at NRC of Canada (39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Hägg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies- are rhombohedral, with space group [Formula: see text]. The certified mean unit cell parameters are a=4.76080±0.00029 Å, and c=12.99568 ű0.00087 Å (expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Hägg transmission measurements on five samples of powdered rubies (a=4.7610 ű0.0013

  7. Standard Reference Material (SRM 1990) for Single Crystal Diffractometer Alignment

    USGS Publications Warehouse

    Wong-Ng, W.; Siegrist, T.; DeTitta, G.T.; Finger, L.W.; Evans, H.T.; Gabe, E.J.; Enright, G.D.; Armstrong, J.T.; Levenson, M.; Cook, L.P.; Hubbard, C.R.

    2001-01-01

    An international project was successfully completed which involved two major undertakings: (1) a round-robin to demonstrate the viability of the selected standard and (2) the certification of the lattice parameters of the SRM 1990, a Standard Reference Material?? for single crystal diffractometer alignment. This SRM is a set of ???3500 units of Cr-doped Al2O3, or ruby spheres [(0 420.011 mole fraction % Cr (expanded uncertainty)]. The round-robin consisted of determination of lattice parameters of a pair of crystals' the ruby sphere as a standard, and a zeolite reference to serve as an unknown. Fifty pairs of crystals were dispatched from Hauptman-Woodward Medical Research Institute to volunteers in x-ray laboratories world-wide. A total of 45 sets of data was received from 32 laboratories. The mean unit cell parameters of the ruby spheres was found to be a=4.7608 A?? ?? 0.0062 A??, and c=12.9979 A?? ?? 0.020 A?? (95 % intervals of the laboratory means). The source of errors of outlier data was identified. The SRM project involved the certification of lattice parameters using four well-aligned single crystal diffractometers at (Bell Laboratories) Lucent Technologies and at NRC of Canada (39 ruby spheres), the quantification of the Cr content using a combined microprobe and SEM/EDS technique, and the evaluation of the mosaicity of the ruby spheres using a double-crystal spectrometry method. A confirmation of the lattice parameters was also conducted using a Guinier-Ha??gg camera. Systematic corrections of thermal expansion and refraction corrections were applied. These rubies_ are rhombohedral, with space group R3c. The certified mean unit cell parameters are a=4.76080 ?? 0.00029 A??, and c=12 99568 A?? ?? 0.00087 A?? (expanded uncertainty). These certified lattice parameters fall well within the results of those obtained from the international round-robin study. The Guinier-Ha??gg transmission measurements on five samples of powdered rubies (a=4.7610 A?? ?? 0

  8. Development of a multi-VOC reference material for quality assurance in materials emission testing.

    PubMed

    Nohr, Michael; Horn, Wolfgang; Jann, Oliver; Richter, Matthias; Lorenz, Wilhelm

    2015-04-01

    Emission test chamber measurement is necessary to proof building materials as sources of volatile organic compounds (VOCs). The results of such measurements are used to evaluate materials and label them according to their potential to emit harmful substances, polluting indoor air. If only labelled materials were installed indoors, this would improve indoor air quality and prevent negative impacts on human health. Because of the complex testing procedure, reference materials for the quality assurance are mandatory. Currently, there is a lack of such materials because most building products show a broad variation of emissions even within one batch. A previous study indicates lacquers, mixed with volatile organic pollutants, as reproducible emission source for a wide range of substances. In the present study, the curing of the lacquer-VOC mixture inside micro-chambers was optimised. Therefore, the humidity and the chamber flow were varied. Typical indoor air pollutants with a wide range of volatilities, for example, styrene, n-hexadecane, dimethyl and dibutyl phthalate were selected. It turned out that, under optimised curing parameters inside the micro-chamber, their emission can be reproduced with variations of less than 10 %. With this, a next important step towards a reference material for emission testing was achieved. PMID:25543146

  9. Development of a multi-VOC reference material for quality assurance in materials emission testing.

    PubMed

    Nohr, Michael; Horn, Wolfgang; Jann, Oliver; Richter, Matthias; Lorenz, Wilhelm

    2015-04-01

    Emission test chamber measurement is necessary to proof building materials as sources of volatile organic compounds (VOCs). The results of such measurements are used to evaluate materials and label them according to their potential to emit harmful substances, polluting indoor air. If only labelled materials were installed indoors, this would improve indoor air quality and prevent negative impacts on human health. Because of the complex testing procedure, reference materials for the quality assurance are mandatory. Currently, there is a lack of such materials because most building products show a broad variation of emissions even within one batch. A previous study indicates lacquers, mixed with volatile organic pollutants, as reproducible emission source for a wide range of substances. In the present study, the curing of the lacquer-VOC mixture inside micro-chambers was optimised. Therefore, the humidity and the chamber flow were varied. Typical indoor air pollutants with a wide range of volatilities, for example, styrene, n-hexadecane, dimethyl and dibutyl phthalate were selected. It turned out that, under optimised curing parameters inside the micro-chamber, their emission can be reproduced with variations of less than 10 %. With this, a next important step towards a reference material for emission testing was achieved.

  10. Development of a Northern Continental Air Standard Reference Material.

    PubMed

    Rhoderick, George C; Kitzis, Duane R; Kelley, Michael E; Miller, Walter R; Hall, Bradley D; Dlugokencky, Edward J; Tans, Pieter P; Possolo, Antonio; Carney, Jennifer

    2016-03-15

    The National Institute of Standards and Technology (NIST) recently began to develop standard mixtures of greenhouse gases as part of a broad program mandated by the 2009 United States Congress to support research in climate change. To this end, NIST developed suites of gravimetrically assigned primary standard mixtures (PSMs) comprising carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in a dry-natural air balance at ambient mole fraction levels. In parallel, the National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado, charged 30 aluminum gas cylinders with northern hemisphere air at Niwot Ridge, Colorado. These mixtures, which constitute NIST Standard Reference Material (SRM) 1720 Northern Continental Air, were certified by NIST for ambient mole fractions of CO2, CH4, and N2O relative to NIST PSMs. NOAA-assigned values are also provided as information in support of the World Meteorological Organization (WMO) Global Atmosphere Watch (GAW) Program for CO2, CH4, and N2O, since NOAA serves as the WMO Central Calibration Laboratory (CCL) for CO2, CH4, and N2O. Relative expanded uncertainties at the 95% confidence interval are <±0.06% of the certified values for CO2 and N2O and <0.2% for CH4, which represents the smallest relative uncertainties specified to date for a gaseous SRM produced by NIST. Agreement between the NOAA (WMO/GAW) and NIST values based on their respective calibration standards suites is within 0.05%, 0.13%, and 0.06% for CO2, CH4, and N2O, respectively. This collaborative development effort also represents the first of its kind for a gaseous SRM developed by NIST. PMID:26890890

  11. Development of a Northern Continental Air Standard Reference Material.

    PubMed

    Rhoderick, George C; Kitzis, Duane R; Kelley, Michael E; Miller, Walter R; Hall, Bradley D; Dlugokencky, Edward J; Tans, Pieter P; Possolo, Antonio; Carney, Jennifer

    2016-03-15

    The National Institute of Standards and Technology (NIST) recently began to develop standard mixtures of greenhouse gases as part of a broad program mandated by the 2009 United States Congress to support research in climate change. To this end, NIST developed suites of gravimetrically assigned primary standard mixtures (PSMs) comprising carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in a dry-natural air balance at ambient mole fraction levels. In parallel, the National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado, charged 30 aluminum gas cylinders with northern hemisphere air at Niwot Ridge, Colorado. These mixtures, which constitute NIST Standard Reference Material (SRM) 1720 Northern Continental Air, were certified by NIST for ambient mole fractions of CO2, CH4, and N2O relative to NIST PSMs. NOAA-assigned values are also provided as information in support of the World Meteorological Organization (WMO) Global Atmosphere Watch (GAW) Program for CO2, CH4, and N2O, since NOAA serves as the WMO Central Calibration Laboratory (CCL) for CO2, CH4, and N2O. Relative expanded uncertainties at the 95% confidence interval are <±0.06% of the certified values for CO2 and N2O and <0.2% for CH4, which represents the smallest relative uncertainties specified to date for a gaseous SRM produced by NIST. Agreement between the NOAA (WMO/GAW) and NIST values based on their respective calibration standards suites is within 0.05%, 0.13%, and 0.06% for CO2, CH4, and N2O, respectively. This collaborative development effort also represents the first of its kind for a gaseous SRM developed by NIST.

  12. Asbestos as reference material for fibre-induced cancer.

    PubMed

    Muhle, H; Pott, F

    2000-06-01

    The objective of this paper is to review published data on the carcinogenicity of asbestos fibres with regard to the elucidation of a potential risk originating from exposure to man-made vitreous fibres (MMVF). Steps in the comparison of the two fibre classes are characterization of the fibres, pulmonary deposition, biodurability and biopersistence and a review of the cancer risk from asbestos fibres after inhalation in rats and humans. Various dust samples of chrysotile, crocidolite, and amosite were used as reference materials in studies with experimental animals. These fibres are normally thinner and shorter than MMVF. These differences in dimensions cause differences in the deposition in the airways. In addition, significant dissimilarities exist in the deposition pattern between rats and humans. Data from biopersistence studies show that focusing only on fibres longer than 20 microm and using weighted half-time for a characterization of risk may be misleading. Inhalation experiments with rats need fibre exposure concentrations over 100 times higher to match the lung cancer risk of asbestos workers, and about 1,000 times higher to reach the same mesothelioma risk. Also, the striking difference between the low lung burden of amphibole fibres of asbestos workers with mesothelioma and the more than 1,000 times higher lung burden of rats with a low mesothelioma risk demonstrates the low sensitivity of the inhalation test model for the carcinogenic potency even of crocidolite fibres. It can be concluded that the rat inhalation model is also not sensitive enough to predict the cancer risk of other fibre types for humans.

  13. 10 CFR 435.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... reference the energy performance standards listed in paragraph (b) of this section into 10 CFR part 435. The... incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to a... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL...

  14. 10 CFR 435.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... reference the energy performance standards listed in paragraph (b) of this section into 10 CFR part 435. The... incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to a... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL...

  15. 10 CFR 435.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... reference the energy performance standards listed in paragraph (b) of this section into 10 CFR part 435. The... incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to a... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL...

  16. Increased sensitivity and variability of phytotoxicity responses in Arctic soils to a reference toxicant, boric acid.

    PubMed

    Anaka, Alison; Wickstrom, Mark; Siciliano, Steven Douglas

    2008-03-01

    Industrial and human activities in the Arctic regions may pose a risk to terrestrial Arctic ecosystem functions. One of the most common terrestrial toxicological end points, primary productivity, typically is assessed using a plant phytotoxicity test. Because of cryoturbation, a soil mixing process common in polar regions, we hypothesized that phytotoxicity test results in Arctic soils would be highly variable compared to other terrestrial ecosystems. The variability associated with phytotoxicity tests was evaluated using Environment Canada's standardized plant toxicity test in three cryoturbated soils from Canada's Arctic exposed to a reference toxicant, boric acid. Northern wheatgrass (Elymus lanceolatus) not only was more sensitive to toxicants in Arctic soils, its response to toxicants was more variable compared to that in temperate soils. The phytotoxicity of boric acid in cryosols was much greater than commonly reported in other soils, with a boric acid concentration of less than 150 microg/g soil needed to inhibit root and shoot growth by 20%. Large variability also was found in the phytotoxicity test results, with coefficients of variation for 10 samples ranging from 160 to 79%. The increased toxicity of boric acid in cryosols and variability in test response was not explained by soil properties. Based on our admittedly limited data set of three different Arctic soils, we recommend that more than 30 samples be taken from each control and potentially impacted area to accurately assess contaminant effects at sites in northern Canada. Such intensive sampling will insure that false-negative results for toxicant impacts in Arctic soils are minimized.

  17. 40 CFR 1045.810 - What materials does this part reference?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... material. Table 1 to this section lists material from the Society of Automotive Engineers that we have... 40 Protection of Environment 34 2013-07-01 2013-07-01 false What materials does this part... Definitions and Other Reference Information § 1045.810 What materials does this part reference?...

  18. 40 CFR 1045.810 - What materials does this part reference?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... material. Table 1 to this section lists material from the Society of Automotive Engineers that we have... 40 Protection of Environment 33 2014-07-01 2014-07-01 false What materials does this part... Definitions and Other Reference Information § 1045.810 What materials does this part reference?...

  19. Contribution for the Derivation of a Soil Screening Value (SSV) for Uranium, Using a Natural Reference Soil

    PubMed Central

    Caetano, Ana Luisa; Marques, Catarina R.; Gavina, Ana; Carvalho, Fernando; Gonçalves, Fernando; da Silva, Eduardo Ferreira; Pereira, Ruth

    2014-01-01

    In order to regulate the management of contaminated land, many countries have been deriving soil screening values (SSV). However, the ecotoxicological data available for uranium is still insufficient and incapable to generate SSVs for European soils. In this sense, and so as to make up for this shortcoming, a battery of ecotoxicological assays focusing on soil functions and organisms, and a wide range of endpoints was carried out, using a natural soil artificially spiked with uranium. In terrestrial ecotoxicology, it is widely recognized that soils have different properties that can influence the bioavailability and the toxicity of chemicals. In this context, SSVs derived for artificial soils or for other types of natural soils, may lead to unfeasible environmental risk assessment. Hence, the use of natural regional representative soils is of great importance in the derivation of SSVs. A Portuguese natural reference soil PTRS1, from a granitic region, was thereby applied as test substrate. This study allowed the determination of NOEC, LOEC, EC20 and EC50 values for uranium. Dehydrogenase and urease enzymes displayed the lowest values (34.9 and <134.5 mg U Kg, respectively). Eisenia andrei and Enchytraeus crypticus revealed to be more sensitive to uranium than Folsomia candida. EC50 values of 631.00, 518.65 and 851.64 mg U Kg were recorded for the three species, respectively. Concerning plants, only Lactuca sativa was affected by U at concentrations up to 1000 mg U kg1. The outcomes of the study may in part be constrained by physical and chemical characteristics of soils, hence contributing to the discrepancy between the toxicity data generated in this study and that available in the literature. Following the assessment factor method, a predicted no effect concentration (PNEC) value of 15.5 mg kg−1dw was obtained for U. This PNEC value is proposed as a SSV for soils similar to the PTRS1. PMID:25353962

  20. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... (b) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part... International Organization for Standardization, Case Postale 56, CH-1211, Geneva 20, Switzerland....

  1. 40 CFR 1068.95 - What materials does this part reference?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air... material from the Society of Automotive Engineers that we have incorporated by reference. The first column... reference it. Anyone may purchase copies of these materials from the Society of Automotive Engineers,...

  2. Blood plasma reference material: a global resource for proteomic research.

    PubMed

    Malm, Johan; Danmyr, Pia; Nilsson, Rolf; Appelqvist, Roger; Végvári, Akos; Marko-Varga, György

    2013-07-01

    There is an ever-increasing awareness and interest within the clinical research field, creating a large demand for blood fraction samples as well as other clinical samples. The translational research area is another field that is demanding for blood samples, used widely in proteomics, genomics, as well as metabolomics. Blood samples are globally the most common biological samples that are used in a broad variety of applications in life science. We hereby introduce a new reference blood plasma standard (heparin) that is aimed as a global resource for the proteomics community. We have developed these reference plasma standards by defining the Control group as those with C-reactive protein levels <3 mg/L and a Disease group with C-reactive protein ranges >30 mg/L. In these references we have used both newborn children 1-2 weeks, as well as youngsters 15-30 years, and middle aged 30-50 years, and elderly patients at the ages of 65+. In total, there were 80 patients in each group in the reference plasma pools. We provide data on the developments and characteristics of the reference blood plasma standards, as well as what is used by the team members at the respective laboratories. The standards have been evaluated by pilot sample processing in biobanking operations and are currently a resource that allows the Proteomic society to perform quantitative proteomic studies. By the use of high quality reference plasma samples, global initiatives, such as the Chromosome Human Proteome Project (C-HPP), will benefit as one scientific program when the entire human proteome is mapped and linked to human diseases. The plasma reference standards are a global resource and can be accessed upon request. PMID:23701512

  3. Spatial uncertainty of the 137Cs reference inventory for Australian soil

    NASA Astrophysics Data System (ADS)

    Chappell, Adrian; Hancock, Gary; Viscarra Rossel, Raphael A.; Loughran, Robert

    2011-12-01

    Soil erosion threatens the productivity of agricultural land, reduces the soil's ability to store water, promotes losses of nutrients, organic matter and soil biota and increases the amount of dust carried by wind. It is difficult to measure directly, particularly over time periods with sufficient duration to represent its variability. The caesium-137 (137Cs) technique estimates net soil redistribution by the combined effect of wind, water and tillage erosion. Used with a single sampling campaign, the 137Cs technique provides retrospective estimates for a given location on medium-term (30-40 years) erosion or deposition rates. In 1990 a national reconnaissance survey of soil erosion in Australia was performed using 137Cs. The aim here is to use the results of that national inventory to establish with spatial uncertainty a preliminary baseline map of the 137Cs reference inventory for Australia to subsequently estimate net (mid 1950s to early 1990s) soil redistribution for Australia. We used an indicator co-simulation between 141 samples of the 137Cs reference inventory and gridded mean annual (1954-1990) rainfall and compared the results with a deterministic method using rainfall and latitude. The former produced a baseline map which reconstructed the spatial data with less bias and smaller uncertainty than the latter. The Australian 137Cs reference inventory map can be improved over time with additional samples and the improved map used for subsequent soil redistribution assessments. Where sufficient data exist the geostatistical method may provide similarly reliable 137Cs reference inventory estimates at unsampled locations around the world.

  4. Characterisation of reference materials for radioactivity with assigned values traceable to the SI units.

    PubMed

    Altzitzoglou, T; Sibbens, G; Bickel, M; Bohnstedt, A; Decaillon, J-G; Hill, C; Holmes, L

    2004-01-01

    The Institute for Reference Materials and Measurements participates in an IAEA co-ordinated project to upgrade Analytical Quality Control Services intercomparison materials to reference materials. The principal objective is to ensure that assigned property values are traceable to the International System of Units. General principles and practical mechanisms for achieving this traceability are described.

  5. 40 CFR 194.13 - Submission of reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROTECTION PROGRAMS CRITERIA FOR THE CERTIFICATION AND RE-CERTIFICATION OF THE WASTE ISOLATION PILOT PLANT'S COMPLIANCE WITH THE 40 CFR PART 191 DISPOSAL REGULATIONS Compliance Certification and Re-certification... reference books need not to be submitted. Whenever possible, DOE shall submit 10 copies of...

  6. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any....ca/onlinestore/welcome.asp. (1) CAN/CSA-C747-94 (“CAN/CSA-C747”) (Reaffirmed 2005), Energy...

  7. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any....ca/onlinestore/welcome.asp. (1) CSA C747-09 (“CSA C747”), Energy efficiency test methods for...

  8. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any....ca/onlinestore/welcome.asp. (1) CSA C747-09 (“CSA C747”), Energy efficiency test methods for...

  9. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... reference. (1) Air-Conditioning and Refrigeration Institute (ARI) Standard 210/240-2003 published in 2003, “Unitary Air-Conditioning and Air-Source Heat Pump Equipment,” IBR approved for § 431.96. (2) ARI Standard 340/360-2004, “Performance Rating of Commercial and Industrial Unitary Air-Conditioning and Heat...

  10. 10 CFR 431.133 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... paragraph (b) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR... Ice-Makers.” (2) American National Standards Institute (ANSI)/American Society of Heating.... Department of Energy, Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies...

  11. 40 CFR 600.011-93 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Factors Engineering Committee, Society of Automotive Engineers, approved September 1973 as revised... 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at the U.S. Environmental Protection.... Document number and name 40 CFR part 600 reference ASTM E 29-67 (Reapproved 1973) Standard...

  12. 10 CFR 431.203 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.... Environmental Protection Agency “ENERGY STAR Program Requirements for Exit Signs,” Version 2.0 issued January 1... Protection Agency “ENERGY STAR Program Requirements for Exit Signs,” Version 2.0, may be obtained from...

  13. 10 CFR 431.203 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.... Environmental Protection Agency “ENERGY STAR Program Requirements for Exit Signs,” Version 2.0 issued January 1... Protection Agency “ENERGY STAR Program Requirements for Exit Signs,” Version 2.0, may be obtained from...

  14. 10 CFR 431.203 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) of this section for incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.... Environmental Protection Agency “ENERGY STAR Program Requirements for Exit Signs,” Version 2.0 issued January 1... Protection Agency “ENERGY STAR Program Requirements for Exit Signs,” Version 2.0, may be obtained from...

  15. 10 CFR 430.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... incorporation by reference by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR.... (2) AATCC Test Method 118-2007, Oil Repellency: Hydrocarbon Resistance Test, Revised 2007, IBR... for Nomenclature for Glass Bulbs—Intended for Use with Electric Lamps, approved March 24, 1994,...

  16. 40 CFR 600.011-93 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Factors Engineering Committee, Society of Automotive Engineers, approved September 1973 as revised... Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be inspected at the U.S... following material is available from the Society of Automotive Engineers. Copies of these materials may...

  17. Gamma ray attenuation in the soils of Northern Ireland, with special reference to peat.

    PubMed

    Beamish, David

    2013-01-01

    This study considers gamma ray attenuation in relation to the soils and bedrock of Northern Ireland using simple theory and data from a high resolution airborne survey. The bedrock is considered as a source of radiogenic material acting as parent to the soil. Attenuation in the near-surface is then controlled by water content in conjunction with the porosity and density of the soil cover. The Total Count radiometric data together with 1:250 k mapping of the soils and bedrock of Northern Ireland are used to perform statistical analyses emphasising the nature of the low count behaviour. Estimations of the bedrock response characteristics are improved by excluding areas covered by low count soils (organic/humic). Equally, estimations of soil response characteristics are improved by excluding areas underlain by low count bedrock (basalt). When the spatial characteristics of the soil-classified data are examined in detail, the low values form spatially-coherent zones (natural clusters) that can potentially be interpreted as areas of increased water content for each soil type. As predicted by theory, the highest attenuation factors are associated with the three organic soil types studied here. Peat, in particular, is remarkably skewed to low count behaviour in its radiometric response. Two detailed studies of blanket bogs reveal the extent to which peat may be mapped by its radiometric response while the intra-peat variations in the observed response may indicate areas of thin cover together with areas of increased water content.

  18. ECUT energy data reference series: lightweight materials for ground transportation

    SciTech Connect

    Abarcar, R.B.; Hane, G.J.; Johnson, D.R.

    1984-07-01

    This report summarizes information that describes the use of lightweight materials in automobiles. The information on this mode of transportation represents the largest potential energy savings for substitution of lightweight materials in the transportation sector. Included are data on energy conversion efficiency of the engine and its relationship to vehicle weight, the capital stock, the amount of energy used, and the service activity level as measured in ton-miles.

  19. USGS Reference Materials Program: Serving the Needs of the Global Analytical Community

    USGS Publications Warehouse

    Wolf, Ruth E.; Wilson, Stephen A.

    2007-01-01

    Every year in the United States, millions of measurements are made on the chemical composition of items that affect us on a daily basis. The accuracy of these measurements is routinely determined by the analysis of appropriate reference materials. In the field of earth science, reference materials are particularly important because they help us develop a better understanding of the processes that have shaped, and continue to shape the world around us. USGS reference materials are distributed internationally to organizations involved in geochemical and environmental analysis, instrumentation and methods development, and industrial research and quality assurance. Reference materials are widely used in the development and validation of geochemical models used by the USGS.

  20. Modification of hydraulic conductivity in granular soils using waste materials.

    PubMed

    Akbulut, S; Saglamer, A

    2004-01-01

    This paper evaluates the use of waste products such as silica fume and fly ash in modification of the granular soils in order to remove some environmental problems and create new useful findings in the field of engineering. It is known that silica fume and fly ash, as well as clay material, are used in geotechnical engineering because of their pozzolanic reactivity and fineness to improve the soil properties needed with respect to engineering purposes. The main objective of this research project was to investigate the use of these materials in geotechnical engineering and to improve the hydraulic properties of soils by means of grouting. For this reason, firstly, suitable grouts in suspension forms were prepared by using silica fume, fly ash, clay and cement in different percentages. The properties of these cement-based grouts were then determined to obtain the desired optimum values for grouting. After that, these grouts were penetrated into the soil samples under pressure. The experimental work indicates that these waste materials and clay improved the physical properties and the fluidity of the cement-based grouts and they also decreased the hydraulic conductivity of the grouted soil samples by sealing the voids of the soil. The results of this study have important findings concerning the use of these materials in soil treatment and the improvement of hydraulic conductivity of the soils. PMID:15120433

  1. Hygrothermal Material Properties for Soils in Building Science

    SciTech Connect

    Pallin, Simon B; Kehrer, Manfred

    2013-01-01

    Hygrothermal performance of soils coupled to buildings is complicated because of the dearth of information on soil properties. However they are important when numerical simulation of coupled heat and moisture transport for below-grade building components are performed as their temperature and moisture content has an influence on the durability of the below-grade building component. Soils can be classified by soil texture. According to the Unified Soil Classification System (USCA), 12 different soils can be defined on the basis of three soil components: clay, sand, and silt. This study shows how existing material properties for typical American soils can be transferred and used for the calculation of the coupled heat and moisture transport of building components in contact with soil. Furthermore a thermal validation with field measurements under known boundary conditions is part of this study, too. Field measurements for soil temperature and moisture content for two specified soils are carried out right now under known boundary conditions. As these field measurements are not finished yet, the full hygrothermal validation is still missing.

  2. delta 15N and non-carbonate delta 13C values for two petroleum source rock reference materials and a marine sediment reference material

    USGS Publications Warehouse

    Dennen, Kristin O.; Johnson, Craig A.; Otter, Marshall L.; Silva, Steven R.; Wandless, Gregory A.

    2006-01-01

    Samples of United States Geological Survey (USGS) Certified Reference Materials USGS Devonian Ohio Shale (SDO-1), and USGS Eocene Green River Shale (SGR-1), and National Research Council Canada (NRCC) Certified Marine Sediment Reference Material (PACS-2), were sent for analysis to four separate analytical laboratories as blind controls for organic rich sedimentary rock samples being analyzed from the Red Dog mine area in Alaska. The samples were analyzed for stable isotopes of carbon (delta13Cncc) and nitrogen (delta15N), percent non-carbonate carbon (Wt % Cncc) and percent nitrogen (Wt % N). SDO-1, collected from the Huron Member of the Ohio Shale, near Morehead, Kentucky, and SGR-1, collected from the Mahogany zone of the Green River Formation are petroleum source rocks used as reference materials for chemical analyses of sedimentary rocks. PACS-2 is modern marine sediment collected from the Esquimalt, British Columbia harbor. The results presented in this study are, with the exceptions noted below, the first published for these reference materials. There are published information values for the elemental concentrations of 'organic' carbon (Wt % Corg measured range is 8.98 - 10.4) and nitrogen (Wt % Ntot 0.347 with SD 0.043) only for SDO-1. The suggested values presented here should be considered 'information values' as defined by the NRCC Institute for National Measurement Reference Materials and should be useful for the analysis of 13C, 15N, C and N in organic material in sedimentary rocks.

  3. Household Hazardous Materials and Their Labels: A Reference for Teachers.

    ERIC Educational Resources Information Center

    Dean, Lillian F.

    Household hazardous materials are products or wastes which are toxic, corrosive, reactive, and/or ignitable. Although common products such as pesticides, oils, gasoline, solvents, cleaners, and polishes are hazardous, students and adults are not always aware of potential dangers. This sourcebook contains definitions and examples of household…

  4. 10 CFR 431.15 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to a standard by the standard-setting....gov/buildings/appliance_standards/. Also, this material is available for inspection at the National... 431. (2) (e) NEMA. National Electrical Manufacturers Association, 1300 North 17th Street, Suite...

  5. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....S.C. 552(a) and 1 CFR part 51. Copies of the materials may be inspected at NHTSA's Docket Section... assembly drawing SA-150 M060, revision A, titled “Pelvis and Abdomen Assembly,” dated May 18, 1994....

  6. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ....S.C. 552(a) and 1 CFR part 51. Copies of the materials may be inspected at NHTSA's Docket Section... assembly drawing SA-150 M060, revision A, titled “Pelvis and Abdomen Assembly,” dated May 18, 1994....

  7. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ....S.C. 552(a) and 1 CFR part 51. Copies of the materials may be inspected at NHTSA's Docket Section... assembly drawing SA-150 M060, revision A, titled “Pelvis and Abdomen Assembly,” dated May 18, 1994....

  8. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ....S.C. 552(a) and 1 CFR part 51. Copies of the materials may be inspected at NHTSA's Docket Section... assembly drawing SA-150 M060, revision A, titled “Pelvis and Abdomen Assembly,” dated May 18, 1994....

  9. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ....S.C. 552(a) and 1 CFR part 51. Copies of the materials may be inspected at NHTSA's Docket Section... assembly drawing SA-150 M060, revision A, titled “Pelvis and Abdomen Assembly,” dated May 18, 1994....

  10. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ....443 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... material is available for inspection at U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, Sixth Floor, 950 L'Enfant Plaza, SW., Washington, DC...

  11. 10 CFR 435.3 - Material incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL LOW-RISE RESIDENTIAL BUILDINGS Mandatory Energy Efficiency Standards for Federal Low-Rise Residential Buildings. § 435... this material by the standard-setting organization will not affect the DOE building energy...

  12. 10 CFR 433.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR THE DESIGN AND... organization will not affect the DOE building energy performance standard unless and until DOE amends its building energy performance standards. DOE incorporates the material as it exists on the date specified...

  13. 10 CFR 435.3 - Material incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL LOW-RISE RESIDENTIAL BUILDINGS Mandatory Energy Efficiency Standards for Federal Low-Rise Residential Buildings. § 435... this material by the standard-setting organization will not affect the DOE building energy...

  14. 10 CFR 433.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR THE DESIGN AND... organization will not affect the DOE building energy performance standard unless and until DOE amends its building energy performance standards. DOE incorporates the material as it exists on the date specified...

  15. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....443 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL... material is available for inspection at U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, Sixth Floor, 950 L'Enfant Plaza, SW., Washington, DC...

  16. 10 CFR 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Any subsequent amendment to this material by..., “Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means... Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the...

  17. 10 CFR 431.303 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to a.... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, (610)...

  18. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to the listed materials by the standard-setting organization will not affect the DOE regulations unless and..., Building Technologies Program, 6th Floor, 950 L'Enfant Plaza SW., Washington, DC 20024, (202) 586-2945,...

  19. 10 CFR 431.263 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to a standard by the standard-setting organization will not affect the DOE regulations unless and until amended by DOE. Material is... Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza...

  20. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Any subsequent amendment to the listed materials by the standard-setting organization will not affect the DOE regulations... Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza SW., Washington, DC...

  1. Collective Bargaining for Public Managers (State and Local): Reference Materials.

    ERIC Educational Resources Information Center

    Civil Service Commission, Washington, DC. Labor Relations Training Center.

    The book contain pertinent articles on various subjects related to collective bargaining. It was developed and the materials specially written for use by instructors in a collective bargaining course designed to assist public sector managers in attaining a stable and productive labor relations environment. Each article has been keyed to the…

  2. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INDUSTRIAL EQUIPMENT Commercial Air Conditioners and Heat Pumps Test Procedures § 431.95 Materials... published in 1998, “Water-source heat pumps—Testing and rating for performance—Part 1: Water-to-air and...) published in 2004, “Standard for Packaged Terminal Air-Conditioners and Heat Pumps,” IBR approved for §...

  3. The Medical Geochemistry of Dusts, Soils, and Other Earth Materials

    NASA Astrophysics Data System (ADS)

    Plumlee, G. S.; Ziegler, T. L.

    2003-12-01

    "Town clenched in suffocating grip of asbestos"USA Today, article on Libby,Montana, February, 2000"Researchers find volcanoes are bad for your health… long after they finish erupting"University of WarwickPress Release, 1999"Toxic soils plague city - arsenic, lead in 5 neighborhoods could imperil 17,000 residents"Denver Post, 2002"Ill winds - dust storms ferry toxic agents between countries and even continents"Science News, 2002A quick scan of newspapers, television, science magazines, or the internet on any given day has a fairly high likelihood of encountering a story (usually accompanied by a creative headline such as those above) regarding human health concerns linked to dusts, soils, or other earth materials. Many such concerns have been recognized and studied for decades, but new concerns arise regularly.Earth scientists have played significant roles in helping the medical community understand some important links between earth materials and human health, such as the role of asbestos mineralogy in disease (Skinner et al., 1988; Ross, 1999; Holland and Smith, 2001), and the role of dusts generated by the 1994 Northridge, California, earthquake in an outbreak of Valley Fever ( Jibson et al., 1998; Schneider et al., 1997).Earth science activities tied to health issues are growing (Skinner and Berger, 2003), and are commonly classified under the emerging discipline of medical geology (Finkelman et al., 2001; Selinus and Frank, 2000; Selinus, in press).Medical geochemistry (also referred to as environmental geochemistry and health: Smith and Huyck (1999), Appleton et al. (1996)) can be considered as a diverse subdiscipline of medical geology that deals with human and animal health in the context of the Earth's geochemical cycle ( Figure 1). Many medical geochemistry studies have focused on how chemical elements in rocks, soils, and sediments are transmitted via water or vegetation into the food chain, and how regional geochemical variations can result in disease

  4. Hygrothermal Simulations of Foundations: Part 1 - Soil Material Properties

    SciTech Connect

    Pallin, Simon B; Kehrer, Manfred

    2013-01-01

    Hygrothermal performance of soils coupled to buildings is a complicated process. The computational approach for heat transfer via the ground is well defined (EN-ISO-13370:, 2007) together with simplified methods (Staszczuk, Radon, & Holm). Though the soil moisture transfer is generally ignored, it is proven not negligible (Janssen, Carmeliet, & Hens, 2004). Even though reliable material properties of soils are required to perform realistic hygrothermal calculations of soils coupled to buildings, such material properties have not been well defined in hygrothermal calculations tools. Typical building constructions which are greatly influenced by soils are basements, crawl spaces and slab on grade and reliable hygrothermal performance of such construction are highly requested; as it is ranked within the top 10 Building America Enclosure Research Ideas according to Enclosures STC - Residential Energy Efficiency Stakeholder Meeting, February 29, 2012 Austin, TX. There exists an extensive amount of measurements on soil properties in Soil Science though this information must be gathered as well as adapted to be applicable in Building Science and for hygrothermal simulation purposes. Soil properties are important when analyzing and designing both new building constructions and retrofitting measures, where the outer boundary of the buildings enclosure consists of soil materials. Concerning basement energy retrofits, interior solutions of improving the energy demand has to cooperate with the existing soil properties and must therefore be designed thereafter. In concerns of exterior retrofits, the soil material can be replaced, if needed, with a more suitable filling material, though this approach applies only for basement walls. The soil material beneath the basement floor can naturally not be replaced hence the soil properties of this part of the buildings enclosure still must be taken into consideration. This study is divided into several parts. The intention of the first

  5. 40 CFR 1060.810 - What materials does this part reference?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Federal Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part.... (a) ASTM material. Table 1 to this section lists material from the American Society for Testing and... these materials from the American Society for Testing and Materials, 100 Barr Harbor Dr., P.O. Box...

  6. 40 CFR 1068.95 - What materials does this part reference?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... material. Table 1 to this section lists material from the Society of Automotive Engineers that we have... 40 Protection of Environment 34 2013-07-01 2013-07-01 false What materials does this part... and Miscellaneous Provisions § 1068.95 What materials does this part reference? Documents listed...

  7. 40 CFR 1068.95 - What materials does this part reference?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... material. Table 1 to this section lists material from the Society of Automotive Engineers that we have... 40 Protection of Environment 33 2014-07-01 2014-07-01 false What materials does this part... and Miscellaneous Provisions § 1068.95 What materials does this part reference? Documents listed...

  8. 40 CFR 1060.810 - What materials does this part reference?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... material. Table 2 to this section lists material from the Society of Automotive Engineers that we have... 40 Protection of Environment 33 2014-07-01 2014-07-01 false What materials does this part... EQUIPMENT Definitions and Other Reference Information § 1060.810 What materials does this part...

  9. Soil attenuation of leachates from low-rank coal combustion wastes: a literature survey. [116 references

    SciTech Connect

    Gauntt, R. O.; DeOtte, R. E.; Slowey, J. F.; McFarland, A. R.

    1984-01-01

    In parallel with pursuing the goal of increased utilization of low-rank solid fuels, the US Department of Energy is investigating various aspects associated with the disposal of coal-combustion solid wastes. Concern has been expressed relative to the potential hazards presented by leachates from fly ash, bottom ash and scrubber wastes. This is of particular interest in some regions where disposal areas overlap aquifer recharge regions. The western regions of the United States are characterized by relatively dry alkaline soils which may effect substantial attenuation of contaminants in the leachates thereby reducing the pollution potential. A project has been initiated to study the contaminant uptake of western soils. This effort consists of two phases: (1) preparation of a state-of-the-art document on soil attenuation; and (2) laboratory experimental studies to characterize attenuation of a western soil. The state-of-the-art document, represented herein, presents the results of studies on the characteristics of selected wastes, reviews the suggested models which account for the uptake, discusses the specialized columnar laboratory studies on the interaction of leachates and soils, and gives an overview of characteristics of Texas and Wyoming soils. 116 references, 10 figures, 29 tables.

  10. [Latin American regional reference materials for porcine heparin and bovine heparin].

    PubMed

    Albertengo, M E; Cinto, R O; Araldi, H T; Vernengo, M J

    1990-02-01

    In agreement with the Regional Programme of Reference Materials of the Panamerican Health Organization the Instituto Nacional de Farmacología y Bromatología of Buenos Aires designed a study for the calibration of a Reference Material for Heparin, porcine, mucosal and a Reference Material for Heparin, bovine, mucosal. The assay methods used in this study were those described in the United States Pharmacopeia XXI Ed and British Pharmacopoeia 1980, Addendum 1983. The overall combined potency estimates of both heparin in preparations relative to 4th Int.St. was 1633.83 UI/ampoule (95% confidence limits 1609.70-1657.96 UI/ampoule) for porcine heparin and 1332.31 UI/ampoule (95% confidence limits, 1302.31-1361.77 UI/ampoule) for bovine heparin. The assigned unitage was 1630 UI/ampoule for the porcine Reference Material and 1330 UI/ampoule for the bovine Reference Material.

  11. Evolutionary design of bone scaffolds with reference to material selection.

    PubMed

    Heljak, M K; Swięszkowski, W; Lam, C X F; Hutmacher, D W; Kurzydłowski, K J

    2012-01-01

    The favourable scaffold for bone tissue engineering should have desired characteristic features, such as adequate mechanical strength and three-dimensional open porosity, which guarantee a suitable environment for tissue regeneration. In fact, the design of such complex structures like bone scaffolds is a challenge for investigators. One of the aims is to achieve the best possible mechanical strength-degradation rate ratio. In this paper we attempt to use numerical modelling to evaluate material properties for designing bone tissue engineering scaffold fabricated via the fused deposition modelling technique. For our studies the standard genetic algorithm was used, which is an efficient method of discrete optimization. For the fused deposition modelling scaffold, each individual strut is scrutinized for its role in the architecture and structural support it provides for the scaffold, and its contribution to the overall scaffold was studied. The goal of the study was to create a numerical tool that could help to acquire the desired behaviour of tissue engineered scaffolds and our results showed that this could be achieved efficiently by using different materials for individual struts. To represent a great number of ways in which scaffold mechanical function loss could proceed, the exemplary set of different desirable scaffold stiffness loss function was chosen.

  12. Soil Inorganic Carbon Formation: Can Parent Material Overcome Climate?

    NASA Astrophysics Data System (ADS)

    Stanbery, C.; Will, R. M.; Seyfried, M. S.; Benner, S. G.; Flores, A. N.; Guilinger, J.; Lohse, K. A.; Good, A.; Black, C.; Pierce, J. L.

    2014-12-01

    Soil carbon is the third largest carbon reservoir and is composed of both organic and inorganic constituents. However, the storage and flux of soil carbon within the global carbon cycle are not fully understood. While organic carbon is often the focus of research, the factors controlling the formation and dissolution of soil inorganic carbon (SIC) are complex. Climate is largely accepted as the primary control on SIC, but the effects of soil parent material are less clear. We hypothesize that effects of parent material are significant and that SIC accumulation will be greater in soils formed from basalts than granites due to the finer textured soils and more abundant calcium and magnesium cations. This research is being conducted in the Reynolds Creek Experimental Watershed (RCEW) in southwestern Idaho. The watershed is an ideal location because it has a range of gradients in precipitation (250 mm to 1200 mm), ecology (sagebrush steppe to juniper), and parent materials (a wide array of igneous and sedimentary rock types) over a relatively small area. Approximately 20 soil profiles will be excavated throughout the watershed and will capture the effects of differing precipitation amounts and parent material on soil characteristics. Several samples at each site will be collected for analysis of SIC content and grain size distribution using a pressure calcimeter and hydrometers, respectively. Initial field data suggests that soils formed over basalts have a higher concentration of SIC than those on granitic material. If precipitation is the only control on SIC, we would expect to see comparable amounts in soils formed on both rock types within the same precipitation zone. However, field observations suggest that for all but the driest sites, soils formed over granite had no SIC detected while basalt soils with comparable precipitation had measurable amounts of SIC. Grain size distribution appears to be a large control on SIC as the sandier, granitic soils promote

  13. Satellite Contamination and Materials Outgassing Knowledgebase - An Interactive Database Reference

    NASA Technical Reports Server (NTRS)

    Green, D. B.; Burns, Dewitt (Technical Monitor)

    2001-01-01

    The goal of this program is to collect at one site much of the knowledge accumulated about the outgassing properties of aerospace materials based on ground testing, the effects of this outgassing observed on spacecraft in flight, and the broader contamination environment measured by instruments on-orbit. We believe that this Web site will help move contamination a step forward, away from anecdotal folklore toward engineering discipline. Our hope is that once operational, this site will form a nucleus for information exchange, that users will not only take information from our knowledge base, but also provide new information from ground testing and space missions, expanding and increasing the value of this site to all. We urge Government and industry users to endorse this approach that will reduce redundant testing, reduce unnecessary delays, permit uniform comparisons, and permit informed decisions.

  14. Background concentrations and reference values for heavy metals in soils of Cuba.

    PubMed

    Alfaro, Mirelys Rodríguez; Montero, Alfredo; Ugarte, Olegario Muñiz; do Nascimento, Clístenes Williams Araújo; de Aguiar Accioly, Adriana Maria; Biondi, Caroline Miranda; da Silva, Ygor Jacques Agra Bezerra

    2015-01-01

    The potential threat of heavy metals to human health has led to many studies on permissible levels of these elements in soils. The objective of this study was to establish quality reference values (QRVs) for Cd, Pb, Zn, Cu, Ni, Cr, Fe, Mn, As, Hg, V, Ba, Sb, Ag, Co, and Mo in soils of Cuba. Geochemical associations between trace elements and Fe were also studied, aiming to provide an index for establishing background concentrations of metals in soils. Surface samples of 33 soil profiles from areas of native forest or minimal anthropic influence were collected. Samples were digested (USEPA method 3051A), and the metals were determined by ICP-OES. The natural concentrations of metals in soils of Cuba followed the order Fe > Mn > Ni > Cr > Ba > V > Zn > Cu > Pb > Co > As > Sb > Ag > Cd > Mo > Hg. The QRVs found for Cuban soils were as follows (mg kg(-1)): Ag (1), Ba (111), Cd (0.6), Co (25), Cr (153), Cu (83), Fe (54,055), Mn (1947), Ni (170), Pb (50), Sb (6), V (137), Zn (86), Mo (0.1), As (19), and Hg (0.1). The average natural levels of heavy metals are above the global average, especially for Ni and Cr. The chemical fractionation of soil samples presenting anomalous concentrations of metals showed that Cu, Ni, Cr, Sb, and As have low bioavailability. This suggests that the risk of contamination of agricultural products via plant uptake is low. However, the final decision on the establishment of soil QRVs in Cuba depends on political, economic, and social issues and in-depth risk analyses considering all routes of exposure to these elements. PMID:25504190

  15. Background concentrations and reference values for heavy metals in soils of Cuba.

    PubMed

    Alfaro, Mirelys Rodríguez; Montero, Alfredo; Ugarte, Olegario Muñiz; do Nascimento, Clístenes Williams Araújo; de Aguiar Accioly, Adriana Maria; Biondi, Caroline Miranda; da Silva, Ygor Jacques Agra Bezerra

    2015-01-01

    The potential threat of heavy metals to human health has led to many studies on permissible levels of these elements in soils. The objective of this study was to establish quality reference values (QRVs) for Cd, Pb, Zn, Cu, Ni, Cr, Fe, Mn, As, Hg, V, Ba, Sb, Ag, Co, and Mo in soils of Cuba. Geochemical associations between trace elements and Fe were also studied, aiming to provide an index for establishing background concentrations of metals in soils. Surface samples of 33 soil profiles from areas of native forest or minimal anthropic influence were collected. Samples were digested (USEPA method 3051A), and the metals were determined by ICP-OES. The natural concentrations of metals in soils of Cuba followed the order Fe > Mn > Ni > Cr > Ba > V > Zn > Cu > Pb > Co > As > Sb > Ag > Cd > Mo > Hg. The QRVs found for Cuban soils were as follows (mg kg(-1)): Ag (1), Ba (111), Cd (0.6), Co (25), Cr (153), Cu (83), Fe (54,055), Mn (1947), Ni (170), Pb (50), Sb (6), V (137), Zn (86), Mo (0.1), As (19), and Hg (0.1). The average natural levels of heavy metals are above the global average, especially for Ni and Cr. The chemical fractionation of soil samples presenting anomalous concentrations of metals showed that Cu, Ni, Cr, Sb, and As have low bioavailability. This suggests that the risk of contamination of agricultural products via plant uptake is low. However, the final decision on the establishment of soil QRVs in Cuba depends on political, economic, and social issues and in-depth risk analyses considering all routes of exposure to these elements.

  16. Hygrothermal Simulation of Foundations: Part 1 - Soil Material Properties

    SciTech Connect

    Kehrer, Manfred; Pallin, Simon B

    2012-10-01

    The hygrothermal performance of soils coupled to buildings is a complicated process. A computational approach for heat transfer through the ground has been well defined (EN ISO 13370:2007, 2007), and simplified methods have been developed (Staszczuk, Radon, and Holm 2010). However, these approaches generally ignore the transfer of soil moisture, which is not negligible (Janssen, Carmeliet, and Hens 2004). This study is divided into several parts. The intention of the first part is to gather, comprehend and adapt soil properties from Soil Science. The obtained information must be applicable to related tasks in Building Science and validated with hygrothermal calculation tools. Future parts of this study will focus on the validation aspect of the soil properties to be implemented. Basic changes in the software code may be requested at this time. Different types of basement construction will be created with a hygrothermal calculation tool, WUFI. Simulations from WUFI will be compared with existing or ongoing measurements. The intentions of the first part of this study have been fulfilled. The soil properties of interest in Building Science have been defined for 12 different soil textures. These properties will serve as input parameters when performing hygrothermal calculations of building constructions coupled to soil materials. The reliability of the soil parameters will be further evaluated with measurements in Part 2.

  17. The automated reference toolset: A soil-geomorphic ecological potential matching algorithm

    USGS Publications Warehouse

    Nauman, Travis; Duniway, Michael C.

    2016-01-01

    Ecological inventory and monitoring data need referential context for interpretation. Identification of appropriate reference areas of similar ecological potential for site comparison is demonstrated using a newly developed automated reference toolset (ART). Foundational to identification of reference areas was a soil map of particle size in the control section (PSCS), a theme in US Soil Taxonomy. A 30-m resolution PSCS map of the Colorado Plateau (366,000 km2) was created by interpolating ∼5000 field soil observations using a random forest model and a suite of raster environmental spatial layers representing topography, climate, general ecological community, and satellite imagery ratios. The PSCS map had overall out of bag accuracy of 61.8% (Kappa of 0.54, p < 0.0001), and an independent validation accuracy of 93.2% at a set of 356 field plots along the southern edge of Canyonlands National Park, Utah. The ART process was also tested at these plots, and matched plots with the same ecological sites (ESs) 67% of the time where sites fell within 2-km buffers of each other. These results show that the PSCS and ART have strong application for ecological monitoring and sampling design, as well as assessing impacts of disturbance and land management action using an ecological potential framework. Results also demonstrate that PSCS could be a key mapping layer for the USDA-NRCS provisional ES development initiative.

  18. Material Properies of Intermediate Materials between Concrete and Gravelly Soil

    NASA Astrophysics Data System (ADS)

    Uchimura, Taro; Kuramochi, Yuko; Thai, Bach Thuan

    Compaction and strength properties of cement-mixed well-graded gravel are studied. Such materials can also be considered as a kind of concrete materials which has much lower cement contents than usual. New concepts on material properties related to their mixture ratio of cement, gravel (aggregate) and water, as well as their compaction density, are proposed, unifying the concepts of geotechnical engineering and concrete engineering. For materials with higher cement contents, the compaction curve becomes flat, with lower maximum compaction density, and higher optimum water contents. The triaxial compressive strength are clearly affected by the dry density, as well as the cement contents.

  19. Immobilization of pentachlorophenol in soil using carbonaceous material amendments.

    PubMed

    Wen, Bei; Li, Rui-Juan; Zhang, Shuzhen; Shan, Xiao-Quan; Fang, Jing; Xiao, Ke; Khan, Shahamat U

    2009-03-01

    In this study, three pentachlorophenol (PCP) laboratory-spiked and one field-contaminated soil were amended with 2.0% char, humic acid (HA) and peat, respectively. The amended soils were aged for either 7 or 250 days. After amendment, CaCl(2) extractability of PCP was significantly decreased. Desorption kinetics indicated that the proposed amendment could lead to a strong binding and slow desorption of PCP in soils. Amendment with char reduced the bioaccumulation factor (BAF) of PCP most significantly for earthworms (Eisenia fetida) in all soils studied. The results of both physicochemical and biological tests suggested that amendment reduced PCP bioavailability quickly and enduringly, implying that carbonaceous material amendment, especially char amendment, was a potentially attractive in situ remediation method for sequestration of PCP in contaminated soil. PMID:19028411

  20. New biological reference materials - in vivo incorporated toxic metals in water hyacinth tissues

    SciTech Connect

    Austin, J.R.; Simon, S.J.; Williams, L.R.; Beckert, W.F.

    1985-06-01

    The purpose of this study was to demonstrate that high-quality reference materials, containing high levels of multiple toxic elements, can be produced with in vivo incorporation procedures. The approach taken was to produce water hyacinth tissue materials - leaves and stems containing high levels of arsenic, cadmium, lead, and mercury - as follows: apply a hydroponic feeding procedure for the in vivo incorporation of toxic elements into water hyacinths; dry, blend, and homogenize the plant materials and determine the levels of the incorporated elements and the homogeneity of the generated plant material; demonstrate that low-level control materials can be successfully blended with high-level materials to yield a homogeneous material with intermediate toxicant levels; evaluate the precision of the analytical methods used to determine toxic element levels in the materials; and evaluate the stability of the resulting materials. Sufficient quantities of the parent materials were produced so that characterized reference materials can now be made available on request. Levels of the toxic elements incorporated in water hyacinth leaves were 100, 300, 60, and 27 times the levels present in the control leaves for arsenic, cadmium, lead, and mercury, respectively. Overall precision of sampling, subsampling, and digestion, and chemical analysis of the treated materials, ranged from 3 to 10% relative standard deviation and was generally comparable to that of three NBS biological reference materials tested. 3 references, 1 figure, 4 tables.

  1. Sorption of bentazone, dichlorprop, MCPA, and propiconazole in reference soils from Norway.

    PubMed

    Thorstensen, C W; Lode, O; Eklo, O M; Christiansen, A

    2001-01-01

    Sorption-desorption kinetic and isotherm studies were performed by the batch equilibrium technique in three Norwegian soils. The soils were a fine sandy loam, a loam, and a soil of highly decomposed organic material. Two commercially formulations were used, Triagran-P and Tilt, containing either a mixture of bentazone [3-isopropyl-1H-2, 1,3-benzothiadiazin-4(3H)-one 2,2-dioxide], dichlorprop [(R)-2-(2, 4-dichlorophenoxy)-propionic acid], and MCPA [(4-chloro-2-methylphenoxy)acetic acid], or propiconazole [(+/-)1-(2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-ylmethyl)-1H-1,2,4-triazole] alone. Sorption-desorption equilibrium occurred within 10 h for all pesticides. The Freundlich isotherms indicated nonlinear sorption of bentazone, dichlorprop, MCPA, and propiconazole. For all pesticides the highest Freundlich adsorption coefficient (K(F)) values were in the soil with highest organic content and lowest pH. For the fine sandy loam and loam, which are representative Norwegian agricultural soils, the results indicate that bentazone, dichlorprop, and MCPA are mobile with KF values ranging from 0.07 to 1.50 mg1-1/n kg(-1) L1/n. Propiconazole is much less mobile with KF values ranging from 27.00 to 36.02 mg1-1/n kg(-1) L1/n in the agricultural soils.

  2. Caesium-137 soil sampling and inventory variability in reference locations: A literature survey

    NASA Astrophysics Data System (ADS)

    Sutherland, Ross A.

    1996-01-01

    Soil sampling design, the number of samples collected and the lateral variation of caesium-137 (137Cs) in uneroded reference locations were extracted from previously published work. The focus was on published work which used 137Cs reference inventory (Bq m-2) for qualitative or quantitative estimation of sediment redistribution (SRD) within the landscape. The objective of this study was to address one of the methodological concerns facing the 137Cs technique - that is, the lack of a rigorous statistical treatment of reference locations. The limited attention paid to the reference location is not justified as true estimates of SRD are based on the assumption of an unbiased, independent, random probability sample estimate, commonly the arithmetic mean. Results from the literature survey indicated that only 11% of the reference locations sampled for 137Cs expressly stated that a probability sampling design was used (transect or systematic-aligned grid). The remaining locations were generally sampled using a non-probability based design, more commonly known as haphazard sampling. Of the 75 reference study areas identified only 40 provided enough information to determine the dispersion around the mean, and from this the coefficient of variation (CV) was calculated for all available data. The median CV was 19·3%, with 95% confidence limits of 13·0-23.4%, indicating that approximately 11 random, independent samples would generally be necessary to adequately quantify the reference 137Cs area activity with an allowable error of 10% at 90% confidence. Further analysis indicated that only one-third of the studies sampled a sufficient number of 137Cs reference locations. This value would actually be lower as sampling frameworks were based on non-probability sampling procedures. For 137Cs reference locations it is recommended that a probability sampling design be utilized, preferably the systematic-aligned grid method, and as a minimum first-order estimate about 11 samples

  3. Copper toxicity in a natural reference soil: ecotoxicological data for the derivation of preliminary soil screening values.

    PubMed

    Caetano, Ana Luísa; Marques, Catarina Ribeiro; Gonçalves, Fernando; da Silva, Eduardo Ferreira; Pereira, Ruth

    2016-01-01

    The risk assessment of contaminated soils is conventionally done with the support of soil screening values (SSVs). Since SSVs are still unavailable for many European countries, including Portugal, standardized toxicity tests are urgently claimed for their derivation. Hence, this work aimed the generation of toxicity values for copper (Cu) in a natural reference soil (PTRS1) targeting different terrestrial species, endpoints and soil functions, as to derive a preliminary Cu SSV. For this, the Assessment Factor approach was applied, which allowed calculating predicted no effect concentrations (PNEC) for Cu that will be the basis for SSV proposal. In order to increase the reliability of the PNEC, and hence of the SSV, a lab/field factor was applied to correct the toxicity values used for PNEC determination. Cu affected urease, cellulase and nitrogen mineralization activities. The EC50 values calculated for the invertebrates reproduction were 130.9, 165.1 and 191.6 mg Cu Kg(-1) soildw for Eisenia andrei, Enchytraeus crypticus and Folsomia candida, respectively. Cu inhibited seed germination mainly for Lactuca sativa, whilst it was toxic for the growth of different plant species (EC50s between 89 and 290.5 mg Cu Kg(-1) soildw). Based on the outcomes gathered, we proposed SSVs for Cu ranging between 26.3 and 31.8 mg Kg(-1) soildw, which is above the background values reported and below all the EC20s recorded for the species and endpoints herein analyzed. Overall, this work describes a procedure that could be easily followed by other European countries wishing to derive SSVs adjusted to their soils. PMID:26520436

  4. Embrapa's experience in the production and development of agriculture reference materials

    NASA Astrophysics Data System (ADS)

    Nogueira, A. R. A.; Souza, G. B.; Bossu, C. M.; Bianchi, S. R.; Verhalen, T. R.; Silva, P. T.; Peixoto, A. A. J.; Silva, C. S.

    2016-07-01

    The main challenge of Embrapa is to develop a model of genuine Brazilian tropical agriculture and livestock. To get this task, the quality of laboratories results is mandatory, increasing the demand for reference materials. Projects were proposed to produce reference materials to support the national agriculture laboratories and consolidate a network able to perform reliable and reproducible analytical testing laboratory within the internationally standards required. Reference materials were produced and available to interested laboratories and collaborative tests were conducted to obtain consensus values. The results and statistical evaluations were performed with the use of software developed by Embrapa Pecuaria Sudeste.

  5. Quality assurance of environmental organic analysis in the absence of certified reference materials

    SciTech Connect

    Hoover, D.; Hamilton, C.; Fowler, B.

    1995-12-31

    Reference materials of characteristic matrix with certified concentrations of analytes are normally cornerstones of analytical quality assurance programs. Environmental analytical chemists face a special challenge in producing accurate and defensible trace analysis data supported by only a limited number of suitable certified reference materials (CRMs) with which to validate methodology. In the absence of CRMs the analyst turns to other means of validating method performance. These may include the use of isotopically labelled standards, matrix spikes, recovery studies, intercalibration exercises and the use of ancillary reference materials. This paper describes the various data validation procedures available with emphasis on understanding and interpretation of the results by data users.

  6. Arsenic species in certified reference material MURST-ISS-A2 (Antarctic krill).

    PubMed

    Grotti, Marco; Soggia, Francesco; Goessler, Walter; Findenig, Silvia; Francesconi, Kevin A

    2010-01-15

    Arsenic compounds were quantified in the certified reference material MURST-ISS-A2 (Antarctic krill) using HPLC/ICPMS. The data should prove useful for assessing the accuracy of arsenic speciation procedures.

  7. REFERENCE MATERIALS AND QUALITY ASSURANCE FOR THE CHARACTERIZATION OF ORGANIC COMPOUNDS IN PARTICULATE MATTER

    EPA Science Inventory

    One of the first environmental matrix Standard Reference Materials (SRMs) developed by the National Institute of Standards and Technology (NIST) for determination of organic species was SRM 1649 Urban Dust, ambient total suspended particulate matter (PM) collected in Washington D...

  8. 40 CFR 1060.810 - What materials does this part reference?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Federal Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part... Materials Document number and name Part 1060reference ASTM D471-06, Standard Test Method for Rubber Property—Effect of Liquids (“ASTM D471”) 1060.515 ASTM D2862-97 (Reapproved 2004), Standard Test Method...

  9. Sixth IASLIC Seminar Papers. Part I: Reference Service-in-Action. Part II: Processing & Servicing of Special Materials in Libraries.

    ERIC Educational Resources Information Center

    Indian Association of Special Libraries & Information Centres, Calcutta (India).

    Part I contains 22 papers covering all aspects of the library reference services including sources of reference materials, an evaluation of reference sources, building a reference collection, training a reference librarian, and the needs of the industrial and medical communities for reference services. All the papers are slanted toward the special…

  10. Methods for TEM analysis of NIST's single-walled carbon nanotube Standard Reference Material

    NASA Astrophysics Data System (ADS)

    Mansfield, Elisabeth; Geiss, Roy; Fagan, Jeffrey A.

    2009-08-01

    The National Institute of Standards and Technology (NIST) will soon release a series of single-walled carbon nanotube (SWCNT) reference materials (RMs) to provide users with a well-characterized material for their applications. The SWCNT reference material will be introduced as a series of three types of material: (1) raw soot characterized for composition, which will be certified as a Standard Reference Material, (2) purified (greater than 90 % SWCNT by weight) bucky paper and (3) dispersed, length-sorted populations characterized by length. The instrumental characterization of NIST's SWCNT reference materials is extensive, and this paper aims to provide researchers with dispersion preparation methods for TEM (transmission electron microscopy) analysis of the SWCNT raw soot. A selection of dispersing solvents, including organic solvents, aqueous surfactants and DNA dispersions, were prepared and examined by TEM. Recommendations for sample preparation of the SWCNT SRM 2483 to yield images similar to those presented here are given. Examples of images of the length-sorted SWCNT reference material are also shown. These results illustrate the importance of optimal dispersion to enable imaging of SWCNT characteristics.

  11. Certification of the European reference soil set (IRMM-443--EUROSOILS). Part I. Adsorption coefficients for atrazine, 2,4-D and lindane.

    PubMed

    Gawlik, B M; Lamberty, A; Pauwels, J; Blum, W E H; Mentler, A; Bussian, B; Eklo, O; Fox, K; Kördel, W; Hennecke, D; Maurer, T; Perrin-Ganier, C; Pflugmacher, J; Romero-Taboada, E; Szabo, G; Muntau, H

    2003-08-01

    The European Commission has characterised and certified a set of six European soils (the EUROSOILS) under the number IRMM-443. After a successful validation and trial period with a preliminary batch it was decided to produce a new batch of certified reference materials. Part I of this paper describes the certification of adsorption coefficients for atrazine, 2,4-D and lindane in these soils. The adsorption coefficients were determined according to OECD Test Guideline 106. Additionally, the underlying principles for the value assignment process according to the GUM and their practical application to the numerical data obtained during the certification exercise according to ISO Guide 34 and 35 are discussed.

  12. Development of a material processing plant for lunar soil

    NASA Technical Reports Server (NTRS)

    Goettsch, Ulix; Ousterhout, Karl

    1992-01-01

    Currently there is considerable interest in developing in-situ materials processing plants for both the Moon and Mars. Two of the most important aspects of developing such a materials processing plant is the overall system design and the integration of the different technologies into a reliable, lightweight, and cost-effective unit. The concept of an autonomous materials processing plant that is capable of producing useful substances from lunar regolith was developed. In order for such a materials processing plant to be considered as a viable option, it must be totally self-contained, able to operate autonomously, cost effective, light weight, and fault tolerant. In order to assess the impact of different technologies on the overall systems design and integration, a one-half scale model was constructed that is capable of scooping up (or digging) lunar soil, transferring the soil to a solar furnace, heating the soil in the furnace to liberate the gasses, and transferring the spent soil to a 'tile' processing center. All aspects of the control system are handled by a 386 class PC via D/A, A/D, and DSP (Digital Signal Processor) control cards.

  13. A Reference List of Audiovisual Materials Produced by the United States Government, 1978.

    ERIC Educational Resources Information Center

    National Archives and Records Service (GSA), Washington, DC. National Audiovisual Center.

    This reference guide describes over 6,000 audiovisual materials selected from more than 10,000 programs produced by 175 federal agencies covering a wide range of subjects, including medicine, dentistry, allied health, education, science, social studies, industrial technology/training, safety, and the environmental sciences. Materials are cited by…

  14. Determination of Perfluorinated Alkyl Acid Concentrations in Biological Standard Reference Materials

    EPA Science Inventory

    Standard reference materials (SRMs) are homogeneous, well-characterized materials used to validate measurements and improve the quality of analytical data. The National Institute of Standards and Technology (NIST) has a wide range of SRMs that have mass fraction values assigned ...

  15. 40 CFR 1045.810 - What materials does this part reference?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone... material. Table 1 to this section lists material from the Society of Automotive Engineers that we have... the Society of Automotive Engineers, 400 Commonwealth Drive, Warrendale, PA 15096 or...

  16. 40 CFR 1068.95 - What materials does this part reference?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may... material. Table 1 to this section lists material from the Society of Automotive Engineers that we have... the Society of Automotive Engineers, 400 Commonwealth Drive, Warrendale, PA 15096 or...

  17. Certificate of Analysis, Standard Reference Material® 1849, Infant/Adult Nutritional Formula

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Standard Reference material (SRM) 1849 is intended primarily for validation of methods for determining proximates, fatty acids, vitamins, elements and nucleotides in infant and adult nutritional formulas and similar materials. This SRM can also be used for quality assurance when assigning values to ...

  18. Sources of Audiovisual Materials about Handicapping Conditions. Reference Circular No. 85-3.

    ERIC Educational Resources Information Center

    Library of Congress, Washington, DC. National Library Service for the Blind and Physically Handicapped.

    The reference circular lists sources of audiovisual materials on handicapping conditions with separate sections on adults and children. The materials, which include films, videocassettes, and slides address such adult-related topics as accessibility, arthritis, attitudes toward disabled persons, communication, deafness, mainstreaming, employment,…

  19. Dissipation of fragrance materials in sludge-amended soils.

    PubMed

    DiFrancesco, Angela M; Chiu, Pei C; Standley, Laurel J; Allen, Herbert E; Salvito, Daniel T

    2004-01-01

    A possible removal mechanism for fragrance materials (FMs) in wastewater is adsorption to sludge, and sludge application to land may be a route through which FMs are released to the soil environment. However, little is known about the concentrations and fate of FMs in soil receiving sludge application. This study was conducted to better understand the dissipation of FMs in sludge-amended soils. We first determined the spiking and extraction efficiencies for 22 FMs in soil and leachate samples. Nine FMs were detected in digested sludges from two wastewater treatment plants in Delaware using these methods. We conducted a 1-year die-away experiment which involved four different soils amended with sludge, with and without spiking of the 22 FMs. The initial dissipation of FMs in all spiked trays was rapid, and only seven FMs remained at concentrations above the quantification limits after 3 months: AHTN, HHCB, musk ketone, musk xylene, acetyl cedrene, OTNE, and DPMI. After 1 year, the only FMs remaining in all spiked trays were musk ketone and AHTN. DPMI was the only FM that leached significantly from the spiked trays, and no FMs were detected in leachate from any unspiked tray. While soil organic matter content affected the dissipation rate in general, different mechanisms (volatilization, transformation, leaching) appeared to be important for different FMs.

  20. Characterization of high-fired PuO/sub 2/ as a certified reference material

    SciTech Connect

    Legeled, M.A.; Cacic, C.G.; Crawford, D.W.; Spaletto, M.I.

    1984-07-01

    The New Brunswick Laboratory (NBL), U.S. Department of Energy, has certified a plutonium dioxide reference material, CRM 122, for plutonium assay and isotopic composition. The PuO/sub 2/ standard, one of several certified Pu reference materials currently being developed at NBL for use in instrumentation calibration and measurement control for safeguards, establishes traceability to the national measurement base. This plutonium reference material in the oxide form provides more directly demonstrable traceability than metal because it undergoes the same chemical treatment for dissolution as PuO/sub 2/ fuel materials. Various tests for achieving a constant weight and for dissolving CRM 122 high-fired PuO/sub 2/ were conducted. Results of these tests as well as the certification data generated by controlled-potential coulometry for plutonium assay and by thermal ionization mass spectrometry for isotopic composition will also be presented and discussed.

  1. EPR-based material modelling of soils considering volume changes

    NASA Astrophysics Data System (ADS)

    Faramarzi, Asaad; Javadi, Akbar A.; Alani, Amir M.

    2012-11-01

    In this paper an approach is presented for developing material models for soils based on evolutionary polynomial regression (EPR), taking into account its volumetric behaviour. EPR is a recently developed hybrid data mining technique that searches for structured mathematical equations (representing the behaviour of a system) using genetic algorithm and the least squares method. Stress-strain data from triaxial test are used to train and develop EPR-based material models for soil. The developed models are compared with some of the well known conventional material models. In particular, the capability of the developed EPR models in predicting volume change behaviour of soils is illustrated. It is also shown that the developed EPR-based material models can be incorporated in finite element (FE) analysis. Two geotechnical examples are presented to verify the developed EPR-based FE model (EPR-FEM). The results of the EPR-FEM are compared with those of a standard FEM where conventional constitutive models are used to describe the material behaviour. The results show that EPR-FEM can be successfully employed to analyse geotechnical engineering problems. The advantages of the proposed EPR models are highlighted.

  2. Infrared optical properties of Mars soil analog materials: Palagonites

    NASA Technical Reports Server (NTRS)

    Roush, Ted L.

    1992-01-01

    The globally distributed bright soils on Mars represent products of chemical alteration of primary igneous materials. As such, understanding the chemistry and mineralogy of these soils provides clues about the nature of the parent materials and the type, duration, and extent of the chemical weathering environments on Mars. Such clues are key in developing an understanding of the interior and surficial processes that have operated throughout Mars' history to yield the surface as it is currently observed. The generally homogeneous nature of these soils is illustrated by a variety of observational data. These data include (1) direct determination of elemental abundances by the X-ray fluorescence instruments on both Viking Landers, (2) Earth-based telescopic observations, and (3) space-based observations. Based on their spectral properties in the visible and near-infrared, terrestrial palagonitic soils have been suggested as analogs for the bright regions on Mars. Palagonites represent the weathering products of basaltic glass and as such are composed of a variety of minerals/materials. In order to gain an understanding regarding the chemical, mineralogical, and spectral properties of a broad suite of palagonites, several samples were collected from the eastern and central regions of the island of Hawaii.

  3. Comparison of phosphate materials for immobilizing cadmium in soil.

    PubMed

    Hong, Chang Oh; Chung, Doug Young; Lee, Do Kyoung; Kim, Pil Joo

    2010-02-01

    A study was conducted to compare the effects of phosphate (P) materials in reducing cadmium extractability. Seven P materials (commercial P fertilizers--fused phosphate (FP), 'fused and superphosphate' [FSP], and rock phosphate [RP]; P chemicals--Ca[H(2)PO(4)](2).H(2)O, [NH(4)](2)HPO(4), KH(2)PO(4), and K(2)HPO(4)) were selected for the test. The selected P source was mixed with Cd-contaminated soil at the rate of 0, 200, 400, 800, and 1,600 mg P kg(-1) under controlled moisture conditions at 70% of water holding capacity, then incubated for 8 weeks. FP, Ca(H(2)PO(4))(2) H(2)O, KH(2)PO(4), and K(2)HPO(4) significantly decreased NH(4)OAc-extractable Cd (plant-available form) concentrations with increasing application rates. Compared to other phosphate materials used, K(2)HPO(4) was found to be the most effective in reducing the plant-available Cd concentration in soil, mainly due to the negative charge increase caused by soil pH and phosphate adsorption. Contrary to the general information, FSP and (NH(4))(2)HPO(4) increased Cd extractability at low levels of P application (<400 mg kg(-1)), and thereafter Cd extractability decreased significantly with increasing application rate. RP scarcely had an effect on reducing Cd extractability. Ion activity products of CdHPO(4), Cd(OH)(2), and CdCO(3) analyzed by the MINTEQ program were significantly increased by K(2)HPO(4) addition, but the effect of Cd-P compound formation on reducing Cd extractability was negligible. Conclusively, the P-induced alleviation of Cd extractability can be attributed primarily to Cd immobilization due to the increase in soil pH and negative charge rather than Cd-P precipitation, and therefore, alkaline P materials such as K(2)HPO(4) are effective for immobilizing soil Cd. PMID:19633979

  4. Production of certified reference materials for the detection of genetically modified organisms.

    PubMed

    Trapmann, Stefanie; Schimmel, Heinz; Kramer, Gerard Nico; Van den Eede, Guy; Pauwels, Jean

    2002-01-01

    Certified reference materials (CRMs) are an essenIial tool in the quality assurance of analytical measurements. They are produced, certified, and used in accordance with relevant ISO (International Organization for Standardization) and BCR (Community Bureau of Reference) guidelines. The Institute for Reference Materials and Measurements (IRMM; Geel, Belgium) has produced the first powdery genetically modified organism (GMO) CRMs in cooperation with the Institute for Health and Consumer Protection (Ispra, Italy). Until now, different weight percentages in the range of 0-5% for 4 GMOs in Europe were produced and certified: Bt (Bacillus thuringiensis)-11 and Bt-176 maize, Roundup Ready soybean, and MON810 maize. Bt-11 and Bt-176 maize and Roundup Ready soybean were produced by IRMM on behalf of Fluka Chemie AG (Buchs, Switzerland). Characterization of used base material is the first step in production and is especially important for GMO CRMs. The production of powdery GMO CRMs and methods used for production control are described. Thorough control of homogeneity and stability are essential for certification of reference materials and ensure validity of the certificate for each bottle of a batch throughout a defined shelf-life. Because production of reference materials and their maintenance are very labor- and cost-intensive tasks, the usefulness of new types of GMO CRMs must be estimated carefully.

  5. Revised delta34S reference values for IAEA sulfur isotope reference materials S-2 and S-3.

    PubMed

    Mann, Jacqueline L; Vocke, Robert D; Kelly, W Robert

    2009-04-01

    Revised delta(34)S reference values with associated expanded uncertainties (95% confidence interval (C.I.)) are presented for the sulfur isotope reference materials IAEA-S-2 (22.62 +/- 0.16 per thousand) and IAEA-S-3 (-32.49 +/- 0.16 per thousand). These revised values are determined using two relative-difference measurement techniques, gas source isotope ratio mass spectrometry (GIRMS) and double-spike multi-collector thermal ionization mass spectrometry (MC-TIMS). Gas analyses have traditionally been considered the most robust for relative isotopic difference measurements of sulfur. The double-spike MC-TIMS technique provides an independent method for value-assignment validation and produces revised values that are both unbiased and more precise than previous value assignments. Unbiased delta(34)S values are required to anchor the positive and negative end members of the sulfur delta (delta) scale because they are the basis for reporting both delta(34)S values and the derived mass-independent Delta(33)S and Delta(36)S values.

  6. Microhomogeneity in reference materials for microanalytical methods - a possible recourse from a blind alley?

    NASA Astrophysics Data System (ADS)

    Renno, A. D.; Michalak, P. P.; Munnik, F.; Tolosana-Delgado, R.; van den Boogaart, G. K.

    2013-12-01

    It is assumed that reference materials for microanalytical methods must be homogeneous, i.e. have the same concentration of the relevant element(s) overall, to ensure that they can be used reliably to get comparison values during the analysis with non absolute methods. With increasing resolution it becomes more and more difficult to ensure such homogeneity, up to the point that it is not possible for several microanalytical methods. Painstaking search for homogeneous natural minerals in gem quality or elaborate expensive methods to produce synthetic minerals provide as obvious solutions to the problem. We propose a way to get reliable reference values with some types of inhomogeneous material, based on multiple probing the reference material. Consider a reference material, which average concentration on the relevant element and its microscale variability has been adequately characterized by a destructive method at a series of grid spots. The minimal number of probing spots required for a certain precision level can be derived from the variance calculations. This procedure is always valid, whenever the heterogeneity value distribution of the reference material has a variance, but at the price that the number of spots will be huge if it is large. However, using adequate models of local heterogeneity can greatly reduce that number. Geostatistics can be used in random, systematic and periodic heterogeneities, while robust methods are useful in cases of nugget heterogeneities. Typical examples of natural and synthetic minerals, analysed by electron microprobe and micro-PIXE (particle induced X-ray emission) for microhomogeneity/microheterogeneity are shown. The distinctions between the two strategies of using these materials as a potential reference material are demonstrated.

  7. Development of new reference materials for the determination of cadmium, chromium, mercury and lead in polycarbonate.

    PubMed

    Lee, Kil Jae; Lee, Yeo Jin; Choi, Young Rak; Kim, Jeong Sook; Kim, Youn Sung; Heo, Soo Bong

    2013-01-01

    Reference materials for quantitative determination of Cd, Cr, Hg and Pb in polycarbonate were developed. Reference materials with two concentration level of elements were prepared by adding appropriate amounts of chemicals to a blank polycarbonate base material. It was shown that ten bottles with triplicate analysis are enough to demonstrate the homogeneity of these candidate reference materials. The statistical results also showed no significant trends in both short-term stability test for four weeks and long-term stability test for twelve months. The certification of the four elements was carried out by isotope-dilution-inductively coupled plasma mass spectrometry (ID-ICP-MS) with microwave-assisted digestion. Certification of candidate reference materials in a single laboratory was confirmed with interlaboratory comparison participated by a certain number of well-recognized testing laboratories in Korea. The certified values and expanded uncertainties (k=2) for the candidate reference material with low level and the one with high level were (51.7±2.1)mgkg(-1) Cd, (103.8±2.9)mgkg(-1) Cd, (98.8±4.5)mgkg(-1) Cr, (1004±49.8)mgkg(-1) Cr, (107.4±4.6)mgkg(-1) Hg, (1133±50.7)mgkg(-1) Hg, (94.8±3.7)mgkg(-1) Pb and (988.4±53.6)mgkg(-1) Pb, respectively. The reference materials developed in this study demonstrated their suitability for the quality assurance in Cd, Cr, Hg and Pb analysis for the implementation of RoHS Directive. PMID:23245892

  8. Synergetic toxic effect of an explosive material mixture in soil.

    PubMed

    Panz, Katarzyna; Miksch, Korneliusz; Sójka, Tadeusz

    2013-11-01

    Explosives materials are stable in soil and recalcitrant to biodegradation. Different authors report that TNT (2,4,6-trinitrotoluene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are toxic, but most investigations have been performed in artificial soil with individual substances. The aim of the presented research was to assess the toxicity of forest soil contaminated with these substances both individually as well in combinations of these substances. TNT was the most toxic substance. Although RDX and HMX did not have adverse effects on plants, these compounds did cause earthworm mortality, which has not been reported in earlier research. Synergistic effects of explosives mixture were observed.

  9. Biological monitoring systems for hazardous waste sites (production and analysis of analytical reference materials)

    SciTech Connect

    Bohman, V.R.; Blincoe, C.R.; Miller, G.C.; Scholl, R.L.; Sutton, W.W.

    1989-02-01

    EPA programs in pesticides, toxics, and hazardous-waste require analytical reference materials. This project emphasized the collection of and analysis of urine, fat, and blood for ultimate use as reference samples and the practicality of using certain metabolites to indicate previous exposure to chlorinated hydrocarbons. The reference samples can, with verified compound concentrations, be used as qualifying samples when evaluating a technique to use for a particular analysis. However, the reference materials may be of greatest benefit when used by laboratories to determine analytical accuracy for samples of human urine, blood, etc. This is because the standards, like the unknown samples, will contain pollutant compounds and associated metabolites (all in vivo incorporated). Dairy animals were used during this study.

  10. Sulphate release from construction and demolition material in soils

    NASA Astrophysics Data System (ADS)

    Abel, Stefan; Wessolek, Gerd

    2013-04-01

    In Berlin and many other cities soils are heavily influenced by anthropogenic activities and deposited substrates. A widespread technical substrate in technosols is construction and demolition material from residential and industrial buildings. Existing rubble landfills without sealing facilities pose threats to ground water quality. In the central city of Berlin rising sulphate concentrations of groundwaters (up to 1200 mg/L) are measured since more than two decades. Previous studies point out that the high sulphate concentrations are mainly attributed to World War II rubble. The major part of debris was deposited in form of landfills and contains approximately 0.3 wt% gypsum. The scope of our research is to determine mechanisms of sulphate release from debris material, interactions between sulphate release, soil hydraulic properties and potential sinks of sulphur. To estimate equilibrium concentration and kinetics of sulphate release of various debris components batch and column experiments are conducted. The same method is applied to determine potential adsorptive character of common debris components. To analyse the impacts of soil hydraulic properties on sulphate leaching we carry out soil column experiments with defined upper and lower boundary conditions, varying water flow velocity and induced preferential flow. Simultaneously we monitor sulphate concentration of soil leachate in a 2 m³ lysimeter. First results of the batch experiments show that gypsum from broken stucco is the main source of sulphate in the observed technosols. Other components as mortar and slag show a quite low sulphate release. Similar results are found within the column experiments. For brigs medium and strongly time dependent sulphate release is determined. Concentrations up to 1500 mg/L are measured in the soil leachate from the lysimeter.

  11. Development of Reference Materials for Thermal-Diffusivity Measurements by the Flash Method

    NASA Astrophysics Data System (ADS)

    Akoshima, M.; Abe, H.; Baba, T.

    2015-12-01

    The thermal conductivity of solid materials used for thermal simulations and thermal designs can be obtained as the product of thermal diffusivity, specific heat capacity, and bulk density in many cases. The thermal diffusivity is usually measured by the flash method, and the specific heat capacity is usually measured by differential scanning calorimetry. In order to obtain reliable thermal conductivities for strict thermal design, it is necessary to measure the thermal diffusivity using the flash method, a well-validated apparatus. Reference materials are an effective means for validation of most practical measurement apparatus. For the flash method, isotropic graphite was selected as a candidate reference material. A batch of isotropic graphite samples was prepared and characterized in detail in order to be a certified reference material for thermal-diffusivity measurement. The detailed characterization ensures the traceability of the measurement results to the international system of units (SI). A convenient reference material for thermal conductivity was also obtained by using the known thermal-diffusivity measurements, specific heat capacity, and density of the material.

  12. High-precision isotopic characterization of USGS reference materials by TIMS and MC-ICP-MS

    NASA Astrophysics Data System (ADS)

    Weis, Dominique; Kieffer, Bruno; Maerschalk, Claude; Barling, Jane; de Jong, Jeroen; Williams, Gwen A.; Hanano, Diane; Pretorius, Wilma; Mattielli, Nadine; Scoates, James S.; Goolaerts, Arnaud; Friedman, Richard M.; Mahoney, J. Brian

    2006-08-01

    The Pacific Centre for Isotopic and Geochemical Research (PCIGR) at the University of British Columbia has undertaken a systematic analysis of the isotopic (Sr, Nd, and Pb) compositions and concentrations of a broad compositional range of U.S. Geological Survey (USGS) reference materials, including basalt (BCR-1, 2; BHVO-1, 2), andesite (AGV-1, 2), rhyolite (RGM-1, 2), syenite (STM-1, 2), granodiorite (GSP-2), and granite (G-2, 3). USGS rock reference materials are geochemically well characterized, but there is neither a systematic methodology nor a database for radiogenic isotopic compositions, even for the widely used BCR-1. This investigation represents the first comprehensive, systematic analysis of the isotopic composition and concentration of USGS reference materials and provides an important database for the isotopic community. In addition, the range of equipment at the PCIGR, including a Nu Instruments Plasma MC-ICP-MS, a Thermo Finnigan Triton TIMS, and a Thermo Finnigan Element2 HR-ICP-MS, permits an assessment and comparison of the precision and accuracy of isotopic analyses determined by both the TIMS and MC-ICP-MS methods (e.g., Nd isotopic compositions). For each of the reference materials, 5 to 10 complete replicate analyses provide coherent isotopic results, all with external precision below 30 ppm (2 SD) for Sr and Nd isotopic compositions (27 and 24 ppm for TIMS and MC-ICP-MS, respectively). Our results also show that the first- and second-generation USGS reference materials have homogeneous Sr and Nd isotopic compositions. Nd isotopic compositions by MC-ICP-MS and TIMS agree to within 15 ppm for all reference materials. Interlaboratory MC-ICP-MS comparisons show excellent agreement for Pb isotopic compositions; however, the reproducibility is not as good as for Sr and Nd. A careful, sequential leaching experiment of three first- and second-generation reference materials (BCR, BHVO, AGV) indicates that the heterogeneity in Pb isotopic compositions

  13. CD Reference Materials Fabricated on Monolithic 200 mm Wafers for Automated Metrology Tool Applications

    NASA Astrophysics Data System (ADS)

    Allen, Richard A.; Dixson, Ronald G.; Cresswell, Michael W.; Guthrie, William F.; Shulver, Byron J. R.; Bunting, A. S.; Stevenson, J. T. M.; Walton, Anthony J.

    2007-09-01

    Recently, prototype isolated-line, single-crystal critical dimension (CD) reference materials (SCCDRMs) with linewidths as narrow as 40 nm±1.5 nm have been reported. These reference materials, designated NIST Prototype Reference Material (RM) 8111, were configured as 10 mm by 11 mm silicon test chips mounted in 200 mm carrier wafers. The RM 8111 chips were fabricated using microelectromechanical (MEMS) process techniques, which assure the alignment of the sidewalls of the features to silicon (111) lattice planes, and were calibrated in a sequence involving atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM) metrology. This paper reports initial results on SCCDRMs fabricated on 200 mm bulk wafers; this monolithic approach would eliminate the need for carrier wafers.

  14. Forming artificial soils from waste materials for mine site rehabilitation

    NASA Astrophysics Data System (ADS)

    Yellishetty, Mohan; Wong, Vanessa; Taylor, Michael; Li, Johnson

    2014-05-01

    Surface mining activities often produce large volumes of solid wastes which invariably requires the removal of significant quantities of waste rock (overburden). As mines expand, larger volumes of waste rock need to be moved which also require extensive areas for their safe disposal and containment. The erosion of these dumps may result in landform instability, which in turn may result in exposure of contaminants such as trace metals, elevated sediment delivery in adjacent waterways, and the subsequent degradation of downstream water quality. The management of solid waste materials from industrial operations is also a key component for a sustainable economy. For example, in addition to overburden, coal mines produce large amounts of waste in the form of fly ash while sewage treatment plants require disposal of large amounts of compost. Similarly, paper mills produce large volumes of alkaline rejected wood chip waste which is usually disposed of in landfill. These materials, therefore, presents a challenge in their use, and re-use in the rehabilitation of mine sites and provides a number of opportunities for innovative waste disposal. The combination of solid wastes sourced from mines, which are frequently nutrient poor and acidic, with nutrient-rich composted material produced from sewage treatment and alkaline wood chip waste has the potential to lead to a soil suitable for mine rehabilitation and successful seed germination and plant growth. This paper presents findings from two pilot projects which investigated the potential of artificial soils to support plant growth for mine site rehabilitation. We found that pH increased in all the artificial soil mixtures and were able to support plant establishment. Plant growth was greatest in those soils with the greatest proportion of compost due to the higher nutrient content. These pot trials suggest that the use of different waste streams to form an artificial soil can potentially be used in mine site rehabilitation

  15. Reference materials and representative test materials to develop nanoparticle characterization methods: the NanoChOp project case

    NASA Astrophysics Data System (ADS)

    Roebben, Gert; Kestens, Vikram; Varga, Zoltan; Charoud-Got, Jean; Ramaye, Yannic; Gollwitzer, Christian; Bartczak, Dorota; Geißler, Daniel; Noble, James; Mazoua, Stéphane; Meeus, Nele; Corbisier, Philippe; Palmai, Marcell; Mihály, Judith; Krumrey, Michael; Davies, Julie; Resch-Genger, Ute; Kumarswami, Neelam; Minelli, Caterina; Sikora, Aneta; Goenaga-Infante, Heidi

    2015-10-01

    This paper describes the production and characteristics of the nanoparticle test materials prepared for common use in the collaborative research project NanoChOp (Chemical and optical characterisation of nanomaterials in biological systems), in casu suspensions of silica nanoparticles and CdSe/CdS/ZnS quantum dots. This paper is the first to illustrate how to assess whether nanoparticle test materials meet the requirements of a 'reference material' (ISO Guide 30:2015) or rather those of the recently defined category of 'representative test material' (ISO TS 16195:2013). The NanoChOp test materials were investigated with small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and centrifugal liquid sedimentation (CLS) to establish whether they complied with the required monomodal particle size distribution. The presence of impurities, aggregates, agglomerates and viable microorganisms in the suspensions was investigated with DLS, CLS, optical and electron microscopy and via plating on nutrient agar. Suitability of surface functionalization was investigated with attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and via the capacity of the nanoparticles to be fluorescently labeled or to bind antibodies. Between-unit homogeneity and stability were investigated in terms of particle size and zeta potential. This paper shows that only based on the outcome of a detailed characterization process one can raise the status of a test material to representative test material or reference material, and how this status depends on its intended use.

  16. Probing soil and aquifer material porosity with nuclear magnetic resonance

    NASA Astrophysics Data System (ADS)

    Hinedi, Z. R.; Kabala, Z. J.; Skaggs, T. H.; Borchardt, D. B.; Lee, R. W. K.; Chang, A. C.

    1993-12-01

    Nuclear magnetic resonance relaxation measurements were used to identify different characteristic porosity domains in soil and aquifer materials. The porosity distribution can be inferred from these measurements by a regularization method applicable to any nuclear magnetic resonance (NMR) relaxation, or by an analytic method applicable only to multiexponential relaxations (D. Orazio et al., 1989). The porosity distribution obtained from NMR relaxation measurements strongly depends on the pore shape factor. For the Borden aquifer material, both the regularized and the analytic pore size distribution obtained from NMR relaxation measurements are consistent with those obtained by Ball et al. (1990) using Hg porosimetry and N2 adsorption. For the Eustis and the Webster soils, the measured porosity domains are qualitatively consistent with those expected based on their respective composition. Our findings suggest that due to the long time required to saturate fine pores, NMR measurements of porosity distribution that are collected at short saturation times are biased toward larger pore sizes.

  17. Development and Characterization of Reference Materials for Genetic Testing: Focus on Public Partnerships.

    PubMed

    Kalman, Lisa V; Datta, Vivekananda; Williams, Mickey; Zook, Justin M; Salit, Marc L; Han, Jin Yeong

    2016-11-01

    Characterized reference materials (RMs) are needed for clinical laboratory test development and validation, quality control procedures, and proficiency testing to assure their quality. In this article, we review the development and characterization of RMs for clinical molecular genetic tests. We describe various types of RMs and how to access and utilize them, especially focusing on the Genetic Testing Reference Materials Coordination Program (Get-RM) and the Genome in a Bottle (GIAB) Consortium. This review also reinforces the need for collaborative efforts in the clinical genetic testing community to develop additional RMs.

  18. Development and Characterization of Reference Materials for Genetic Testing: Focus on Public Partnerships.

    PubMed

    Kalman, Lisa V; Datta, Vivekananda; Williams, Mickey; Zook, Justin M; Salit, Marc L; Han, Jin Yeong

    2016-11-01

    Characterized reference materials (RMs) are needed for clinical laboratory test development and validation, quality control procedures, and proficiency testing to assure their quality. In this article, we review the development and characterization of RMs for clinical molecular genetic tests. We describe various types of RMs and how to access and utilize them, especially focusing on the Genetic Testing Reference Materials Coordination Program (Get-RM) and the Genome in a Bottle (GIAB) Consortium. This review also reinforces the need for collaborative efforts in the clinical genetic testing community to develop additional RMs. PMID:27578503

  19. Molecular diagnostics: harmonization through reference materials, documentary standards and proficiency testing.

    PubMed

    Holden, Marcia J; Madej, Roberta M; Minor, Philip; Kalman, Lisa V

    2011-09-01

    There is a great need for harmonization in nucleic acid testing for infectious disease and clinical genetics. The proliferation of assay methods, the number of targets for molecular diagnostics and the absence of standard reference materials contribute to variability in test results among laboratories. This article provides a comprehensive overview of reference materials, related documentary standards and proficiency testing programs. The article explores the relationships among these resources and provides necessary information for people practicing in this area that is not taught in formal courses and frequently is obtained on an ad hoc basis. The aim of this article is to provide helpful tools for molecular diagnostic laboratories.

  20. Evaluation of homogeneity of a certified reference material by instrumental neutron activation analysis

    SciTech Connect

    Kratochvil, B.; Duke, M.J.M.; Ng, D.

    1986-01-01

    The homogeneity of the marine reference material TORT-1, a spray-dried and acetone-extracted hepatopancreatic material from the lobster, was tested for 26 elements by instrumental neutron activation analysis (INAA). Through a one-way analysis of variance based on six analyses on each of six bottles of TORT-1, it was concluded that the between-bottle heterogeneity is no greater than the within-bottle heterogeneity. The analytical results for those elements for which values were provided by NRC agree with the NRC values within 95% confidence limits. 8 references, 6 tables.

  1. Development and Characterization of Reference Materials for Genetic Testing: Focus on Public Partnerships

    PubMed Central

    Kalman, Lisa V.; Datta, Vivekananda; Williams, Mickey; Zook, Justin M.; Salit, Marc L.

    2016-01-01

    Characterized reference materials (RMs) are needed for clinical laboratory test development and validation, quality control procedures, and proficiency testing to assure their quality. In this article, we review the development and characterization of RMs for clinical molecular genetic tests. We describe various types of RMs and how to access and utilize them, especially focusing on the Genetic Testing Reference Materials Coordination Program (Get-RM) and the Genome in a Bottle (GIAB) Consortium. This review also reinforces the need for collaborative efforts in the clinical genetic testing community to develop additional RMs. PMID:27578503

  2. Assessment of international reference materials for isotope-ratio analysis (IUPAC Technical Report)

    USGS Publications Warehouse

    Brand, Willi A.; Coplen, Tyler B.; Vogl, Jochen; Rosner, Martin; Prohaska, Thomas

    2014-01-01

    Since the early 1950s, the number of international measurement standards for anchoring stable isotope delta scales has mushroomed from 3 to more than 30, expanding to more than 25 chemical elements. With the development of new instrumentation, along with new and improved measurement procedures for studying naturally occurring isotopic abundance variations in natural and technical samples, the number of internationally distributed, secondary isotopic reference materials with a specified delta value has blossomed in the last six decades to more than 150 materials. More than half of these isotopic reference materials were produced for isotope-delta measurements of seven elements: H, Li, B, C, N, O, and S. The number of isotopic reference materials for other, heavier elements has grown considerably over the last decade. Nevertheless, even primary international measurement standards for isotope-delta measurements are still needed for some elements, including Mg, Fe, Te, Sb, Mo, and Ge. It is recommended that authors publish the delta values of internationally distributed, secondary isotopic reference materials that were used for anchoring their measurement results to the respective primary stable isotope scale.

  3. Development and certification of green tea-containing standard reference materials.

    PubMed

    Sander, L C; Bedner, M; Tims, M C; Yen, J H; Duewer, D L; Porter, B; Christopher, S J; Day, R D; Long, S E; Molloy, J L; Murphy, K E; Lang, B E; Lieberman, R; Wood, L J; Payne, M J; Roman, M C; Betz, J M; NguyenPho, A; Sharpless, K E; Wise, S A

    2012-01-01

    A suite of three green tea-containing Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST): SRM 3254 Camellia sinensis (Green Tea) Leaves, SRM 3255 Camellia sinensis (Green Tea) Extract, and SRM 3256 Green Tea-Containing Solid Oral Dosage Form. The materials are characterized for catechins, xanthine alkaloids, theanine, and toxic elements. As many as five methods were used in assigning certified and reference values to the constituents, with measurements carried out at NIST and at collaborating laboratories. The materials are intended for use in the development and validation of new analytical methods, and for use as control materials as a component in the support of claims of metrological traceability. PMID:22127575

  4. Parental material and cultivation determine soil bacterial community structure and fertility.

    PubMed

    Sun, Li; Gao, Jusheng; Huang, Ting; Kendall, Joshua R A; Shen, Qirong; Zhang, Ruifu

    2015-01-01

    Microbes are the key components of the soil environment, playing important roles during soil development. Soil parent material provides the foundation elements that comprise the basic nutritional environment for the development of microbial community. After 30 years artificial maturation of cultivation, the soil developments of three different parental materials were evaluated and bacterial community compositions were investigated using the high-throughput sequencing approach. Thirty years of cultivation increased the soil fertility and soil microbial biomass, richness and diversity, greatly changed the soil bacterial communities, the proportion of phylum Actinobacteria decreased significantly, while the relative abundances of the phyla Acidobacteria, Chloroflexi, Gemmatimonadetes, Armatimonadetes and Nitrospira were significantly increased. Soil bacterial communities of parental materials were separated with the cultivated ones, and comparisons of different soil types, granite soil and quaternary red clay soil were similar and different with purple sandy shale soil in both parental materials and cultivated treatments. Bacterial community variations in the three soil types were affected by different factors, and their alteration patterns in the soil development also varied with soil type. Soil properties (except total potassium) had a significant effect on the soil bacterial communities in all three soil types and a close relationship with abundant bacterial phyla. The amounts of nitrogen-fixing bacteria as well as the abundances of the nifH gene in all cultivated soils were higher than those in the parental materials; Burkholderia and Rhizobacte were enriched significantly with long-term cultivation. The results suggested that crop system would not deplete the nutrients of soil parental materials in early stage of soil maturation, instead it increased soil fertility and changed bacterial community, specially enriched the nitrogen-fixing bacteria to accumulate

  5. Parental material and cultivation determine soil bacterial community structure and fertility.

    PubMed

    Sun, Li; Gao, Jusheng; Huang, Ting; Kendall, Joshua R A; Shen, Qirong; Zhang, Ruifu

    2015-01-01

    Microbes are the key components of the soil environment, playing important roles during soil development. Soil parent material provides the foundation elements that comprise the basic nutritional environment for the development of microbial community. After 30 years artificial maturation of cultivation, the soil developments of three different parental materials were evaluated and bacterial community compositions were investigated using the high-throughput sequencing approach. Thirty years of cultivation increased the soil fertility and soil microbial biomass, richness and diversity, greatly changed the soil bacterial communities, the proportion of phylum Actinobacteria decreased significantly, while the relative abundances of the phyla Acidobacteria, Chloroflexi, Gemmatimonadetes, Armatimonadetes and Nitrospira were significantly increased. Soil bacterial communities of parental materials were separated with the cultivated ones, and comparisons of different soil types, granite soil and quaternary red clay soil were similar and different with purple sandy shale soil in both parental materials and cultivated treatments. Bacterial community variations in the three soil types were affected by different factors, and their alteration patterns in the soil development also varied with soil type. Soil properties (except total potassium) had a significant effect on the soil bacterial communities in all three soil types and a close relationship with abundant bacterial phyla. The amounts of nitrogen-fixing bacteria as well as the abundances of the nifH gene in all cultivated soils were higher than those in the parental materials; Burkholderia and Rhizobacte were enriched significantly with long-term cultivation. The results suggested that crop system would not deplete the nutrients of soil parental materials in early stage of soil maturation, instead it increased soil fertility and changed bacterial community, specially enriched the nitrogen-fixing bacteria to accumulate

  6. Using Photon Activation Analysis To Determine Concentrations Of Unknown Components In Reference Materials

    SciTech Connect

    Green, Jaromy; Sun, Zaijing; Wells, Doug; Maschner, Herb

    2011-06-01

    Using certified multi-element reference materials for instrumental analyses one frequently is confronted with the embarrassing fact that the concentration of some desired elements are not given in the respective certificate, nonetheless are detectable, e.g. by photon activation analysis (PAA). However, these elements might be determinable with sufficient quality of the results using scaling parameters and the well-known quantities of a reference element within the reference material itself. Scaling parameters include: activation threshold energy, Giant Dipole Resonance (GDR) peak and endpoint energy of the bremsstrahlung continuum; integrated photo-nuclear cross sections for the isotopes of the reference element; bremsstrahlung continuum integral; target thickness; photon flux density. Photo-nuclear cross sections from the unreferenced elements must be known, too. With these quantities, the integral was obtained for both the known and unknown elements resulting in an inference of the concentration of the unreported element based upon the reported value, thus also the concentration of the unreferenced element in the reference material. A similar method to determine elements using the basic nuclear and experimental data has been developed for thermal neutron activation analysis some time ago (k{sub 0} Method).

  7. Homogeneity study of a corn flour laboratory reference material candidate for inorganic analysis.

    PubMed

    Dos Santos, Ana Maria Pinto; Dos Santos, Liz Oliveira; Brandao, Geovani Cardoso; Leao, Danilo Junqueira; Bernedo, Alfredo Victor Bellido; Lopes, Ricardo Tadeu; Lemos, Valfredo Azevedo

    2015-07-01

    In this work, a homogeneity study of a corn flour reference material candidate for inorganic analysis is presented. Seven kilograms of corn flour were used to prepare the material, which was distributed among 100 bottles. The elements Ca, K, Mg, P, Zn, Cu, Fe, Mn and Mo were quantified by inductively coupled plasma optical emission spectrometry (ICP OES) after acid digestion procedure. The method accuracy was confirmed by analyzing the rice flour certified reference material, NIST 1568a. All results were evaluated by analysis of variance (ANOVA) and principal component analysis (PCA). In the study, a sample mass of 400mg was established as the minimum mass required for analysis, according to the PCA. The between-bottle test was performed by analyzing 9 bottles of the material. Subsamples of a single bottle were analyzed for the within-bottle test. No significant differences were observed for the results obtained through the application of both statistical methods. This fact demonstrates that the material is homogeneous for use as a laboratory reference material.

  8. PAHs in baby food: assessment of three different processing techniques for the preparation of reference materials.

    PubMed

    Huertas-Pérez, José Fernando; Bordajandi, Luisa R; Sejerøe-Olsen, Berit; Emteborg, Håkan; Baù, Andrea; Schimmel, Heinz; Dabrio, Marta

    2015-04-01

    A feasibility study for producing a matrix reference material for selected polycyclic aromatic hydrocarbons (PAHs) in baby food is reported. A commercially available baby food, containing carrots, potatoes, tomato, white beans and meat, was spiked with the so-called 15 + 1 PAHs included in the PAHs priority list for food of the EU, at a mass fraction level of 1 μg/kg. The contaminated baby food was further processed by autoclaving, freezing or freeze drying. The homogeneity of the three materials (bottle-to-bottle variation) and their short-term (4 weeks) and long-term (18 months) stability at different temperatures were assessed. To this end, an analytical method based on a solid-liquid extraction followed by cleaning up with gel permeation chromatography (GPC) and solid phase extraction (SPE) and GC-IDMS determination, was validated in-house. It could be demonstrated that the procedure fulfilled the demands for application to the homogeneity and isochronous stability studies for the candidate reference materials targeted here. All three materials proved to be sufficiently homogeneous for the intended use. Measurements on the autoclaved material provided the most promising results in terms of envisaged shelf life, although freeze drying was also found to be a suitable processing technique for most of the investigated PAHs. These results are an important step towards the development of a matrix reference material for PAHs in a processed food matrix in a presentation very similar to routine samples.

  9. Development of a mushroom powder Certified Reference Material for calcium, arsenic, cadmium and lead measurements.

    PubMed

    Chew, Gina; Sim, Lay Peng; Ng, Sin Yee; Ding, Yi; Shin, Richard Y C; Lee, Tong Kooi

    2016-01-01

    Isotope dilution mass spectrometry and standard addition techniques were developed for the analysis of four elements (Ca, As, Cd and Pb) in a mushroom powder material. Results from the validated methods were compared to those of other national metrology institutes in the CCQM-K89 intercomparisons and the results were in excellent agreement with the reference values. The same methods were then used for the assignment of reference values to a mushroom powder Certified Reference Material (CRM). The certified values obtained for Ca, As, Cd and Pb were 1.444 ± 0.099 mg/g, 5.61 ± 0.59 mg/kg, 1.191 ± 0.079 mg/kg and 5.23 ± 0.94 mg/kg, respectively. The expanded measurement uncertainties were obtained by combining the uncertainty contributions from characterization (uchar) and between-bottle homogeneity (ubb).

  10. Analysis of marine sediment and lobster hepatopancreas reference materials by instrumental photon activation

    SciTech Connect

    Landsberger, S.; Davidson, W.F.

    1985-01-01

    By use of instrumental photon activation analysis, twelve trace (As, Ba, Cr, Co, Mn, Ni, Pb, Sb, Sr, U, Zn, and Zr) and eight minor (C, Na, Mg, Co, K, Ca, Tl, and Fe) elements were determined in a certified marine sediment standard reference material as well as eight trace (Mn, Ni, Cu, Zn, As, Sr, Cd, and Pb) and four minor (Na, Mg, Cl, and Ca) elements in a certified marine tissue (lobster hepatopancreas) standard reference material. The precision and accuracy of the present results when compared to the accepted values clearly demonstrate the reliability of this nondestructive technique and its applicability to marine environmental or marine geochemical studies. 24 references, 4 figures, 3 tables.

  11. Reference Materials for Food and Nutrition Metrology: Past, Present and Future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Establishment of a metrology-based measurement system requires the solid foundation of traceability of measurements to available, appropriate certified reference materials (CRM). In the early 1970’s the first “biological” RM of Bowens Kale, as well as Orchard Leaves and Bovine Liver SRMs, from the ...

  12. 40 CFR 1045.810 - What materials does this part reference?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone... Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go...

  13. Sources of Braille Reading Materials. Reference Circular No. 86-2.

    ERIC Educational Resources Information Center

    Redmond, Linda, Comp.

    This reference circular lists sources of braille books available for loan, purchase, rental, or free (give-away) distribution. Divided into four sections, it includes general sources of braille books, sources of specialized braille materials, the major braille presses, and resources for further information about braille books and magazines.…

  14. 40 CFR 1048.810 - What materials does this part reference?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone..., Switzerland or http://www.iso.org. Table 2 follows: Table 2 of § 1048.810—ISO Materials Document number...

  15. 40 CFR 1048.810 - What materials does this part reference?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone..., Switzerland or http://www.iso.org. Table 2 follows: Table 2 of § 1048.810—ISO Materials Document number...

  16. 40 CFR 1048.810 - What materials does this part reference?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Register approved the incorporation by reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone..., Switzerland or http://www.iso.org. Table 2 follows: Table 2 of § 1048.810—ISO Materials Document number...

  17. New matrix-free reference material for ethene in the form of optical fibres.

    PubMed

    Słomińska, Marta; Konieczka, Piotr; Namieśnik, Jacek

    2013-02-01

    Reference materials are indispensable in the quality control and quality assurance of analytical measurements. One novel approach to the generation of standard gaseous mixtures of toxic, reactive, volatile, labile, and malodorous substances involves thermal decomposition or rearrangement, under defined temperature conditions, of compounds immobilized, by chemical bonding, on the surface of an appropriate carrier to release specific amounts of a volatile compound. In this technique the type of support used to immobilize the compound is extremely important, because the amount of analyte released depends directly on the choice of material. In this paper we report the novel preparation of a matrix-free ethene standard in the form of glass fibres coated with a thin layer of aluminium, the surface of which is modified by reaction with a specific compound. As a result of thermal decomposition of this compound, gaseous ethene is formed. In this paper we present the results obtained from tests of stability and homogeneity, two properties of crucial importance in the preparation of reference materials, by comparison of a series of results obtained for randomly chosen samples of the reference material. Interlaboratory comparative studies resulted in determination of a reference value for the ethene formed after thermal decomposition of the surface compound ((2.12 ± 0.14) ng per fibre). PMID:23239177

  18. Doorways III: Teacher Reference Materials. On School-Related Gender-Based Violence Prevention and Response

    ERIC Educational Resources Information Center

    US Agency for International Development, 2009

    2009-01-01

    The Doorways training program was designed by the U.S. Agency for International Development (USAID)-funded Safe Schools Program (Safe Schools) to enable teachers, community members and students to prevent and respond to school-related gender-based violence (SRGBV). This booklet, "Doorways III: Teacher Reference Materials on School-Related…

  19. 40 CFR 1068.95 - What materials does this part reference?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... reference as prescribed in 5 U.S.C. 552(a) and 1 CFR part 51. Anyone may inspect copies at the U.S. EPA, Air.../code_of_federal_regulations/ibr_locations.html. (a) SAE material. Table 1 to this section lists... Commonwealth Drive, Warrendale, PA 15096 or http://www.sae.org. Table 1 follows: Table 1 to §...

  20. Development of a new cucumber reference material for pesticide residue analysis: feasibility study for material processing, homogeneity and stability assessment.

    PubMed

    Grimalt, Susana; Harbeck, Stefan; Shegunova, Penka; Seghers, John; Sejerøe-Olsen, Berit; Emteborg, Håkan; Dabrio, Marta

    2015-04-01

    The feasibility of the production of a reference material for pesticide residue analysis in a cucumber matrix was investigated. Cucumber was spiked at 0.075 mg/kg with each of the 15 selected pesticides (acetamiprid, azoxystrobin, carbendazim, chlorpyrifos, cypermethrin, diazinon, (α + β)-endosulfan, fenitrothion, imazalil, imidacloprid, iprodione, malathion, methomyl, tebuconazole and thiabendazole) respectively. Three different strategies were considered for processing the material, based on the physicochemical properties of the vegetable and the target pesticides. As a result, a frozen spiked slurry of fresh cucumber, a spiked freeze-dried cucumber powder and a freeze-dried cucumber powder spiked by spraying the powder were studied. The effects of processing and aspects related to the reconstitution of the material were evaluated by monitoring the pesticide levels in the three materials. Two separate analytical methods based on LC-MS/MS and GC-MS/MS were developed and validated in-house. The spiked freeze-dried cucumber powder was selected as the most feasible material and more exhaustive studies on homogeneity and stability of the pesticide residues in the matrix were carried out. The results suggested that the between-unit homogeneity was satisfactory with a sample intake of dried material as low as 0.1 g. A 9-week isochronous stability study was undertaken at -20 °C, 4 °C and 18 °C, with -70 °C designated as the reference temperature. The pesticides tested exhibited adequate stability at -20 °C during the 9-week period as well as at -70 °C for a period of 18 months. These results constitute a good basis for the development of a new candidate reference material for selected pesticides in a cucumber matrix. PMID:25627789

  1. Reference materials and representative test materials to develop nanoparticle characterization methods: the NanoChOp project case

    PubMed Central

    Roebben, Gert; Kestens, Vikram; Varga, Zoltan; Charoud-Got, Jean; Ramaye, Yannic; Gollwitzer, Christian; Bartczak, Dorota; Geißler, Daniel; Noble, James; Mazoua, Stephane; Meeus, Nele; Corbisier, Philippe; Palmai, Marcell; Mihály, Judith; Krumrey, Michael; Davies, Julie; Resch-Genger, Ute; Kumarswami, Neelam; Minelli, Caterina; Sikora, Aneta; Goenaga-Infante, Heidi

    2015-01-01

    This paper describes the production and characteristics of the nanoparticle test materials prepared for common use in the collaborative research project NanoChOp (Chemical and optical characterization of nanomaterials in biological systems), in casu suspensions of silica nanoparticles and CdSe/CdS/ZnS quantum dots (QDs). This paper is the first to illustrate how to assess whether nanoparticle test materials meet the requirements of a “reference material” (ISO Guide 30, 2015) or rather those of the recently defined category of “representative test material (RTM)” (ISO/TS 16195, 2013). The NanoChOp test materials were investigated with small-angle X-ray scattering (SAXS), dynamic light scattering (DLS), and centrifugal liquid sedimentation (CLS) to establish whether they complied with the required monomodal particle size distribution. The presence of impurities, aggregates, agglomerates, and viable microorganisms in the suspensions was investigated with DLS, CLS, optical and electron microscopy and via plating on nutrient agar. Suitability of surface functionalization was investigated with attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and via the capacity of the nanoparticles to be fluorescently labeled or to bind antibodies. Between-unit homogeneity and stability were investigated in terms of particle size and zeta potential. This paper shows that only based on the outcome of a detailed characterization process one can raise the status of a test material to RTM or reference material, and how this status depends on its intended use. PMID:26539428

  2. Airborne particulate soiling of terrestrial photovoltaic modules and cover materials

    NASA Technical Reports Server (NTRS)

    Hoffman, A. R.; Maag, C. R.

    1980-01-01

    Results are presented for the first phase of a photovoltaic-module soiling study that was carried out with NASA participation to investigate the problem of the electrical performance degradation of flat-plate photovoltaic modules exposed at outdoor sites that is due to the accumulation of airborne particulates on sensitive optical surfaces. The results were obtained in both field and laboratory soiling experiments, as well as in materials field experiments using candidate encapsulants and top covers. It is concluded that: (1) the electrical performance degradation shows a significant time and site dependence, ranging from 2% to 60% power loss; (2) the rate of particulate accumulation appears to be largely material independent when natural removal processes do not dominate; (3) the effectiveness of natural removal processes, especially rain, is strongly material dependent; (4) top-cover materials of glass and plexiglass retain fewer particles than silicone rubber; and (5) high module voltages relative to ground do not appear to affect the rate of dirt accumulation on modules.

  3. Soil Materials and Health: An new experience for teaching

    NASA Astrophysics Data System (ADS)

    Del Hoyo Martínez, Carmen

    2014-05-01

    Cationic clays are very extended compounds on the earth surface so they constitute the main component of soils and sedimentary rocks. Due to their presence and special properties that they have, mankind has used them with therapeutic aims from Prehistory, not being rare to find references to this subject in works of classic authors. During the Renaissance and with the appearance of the first Pharmacopeia, its use was regulated to a certain extent. The scientific development reached during the XXth century has allowed to understand and to study the reasons of the useful and peculiar properties of clays, directly related to their colloidal size and crystalline structure. These properties are translated in a high specific surface area, optimal rheological properties and/or excellent sorptive capacity; everything makes cationic clays very useful for a wide range of applications. In the field of health, cationic clays are used in Pharmaceutical Technology and Dermopharmacy as ideal excipients and substances of suitable biological activity due to their chemical inertness and low or null toxicity for the patient (Carretero, 2002; Lopez Galindo et al., 2005; Choy et al., 2007; del Hoyo, 2007). Cationic clays can be used in a wide range of applications in health. However, it must be also considered that the risk exposure to cationic clays may cause several diseases, as it has been seen above. Cationic clays have been used as excipients and active principles in the pharmaceutical industry. The last tendencies are their use in geomedicine, as much to come up as to treat diseases. One stands out his presence in spas and aesthetic medicine. Development of new pharmaceutical formulations is observed, based on cationic clays, for cancer therapy. It has to emphasize the importance in the synthesis of biosensors with cationic clays. Cationic clays can be considered a group of promising materials in the development of new health applications. The study of the use of the cationic

  4. Measurements of plutonium, 237Np, and 137Cs in the BCR 482 lichen reference material

    DOE PAGES

    Lavelle, Kevin B.; Miller, Jeffrey L.; Hanson, Susan K.; Connick, William B.; Spitz, Henry B.; Glover, Samuel E.; Oldham, Warren J.

    2015-10-01

    Select anthropogenic radionuclides were measured in lichen reference material, BCR 482. This material was originally collected in Axalp, Switzerland in 1991 and is composed of the epiphytic lichen Pseudevernia furfuracea. Samples from three separate bottles of BCR 482 were analyzed for uranium, neptunium, and plutonium isotopes by inductively coupled plasma mass spectrometry (ICP-MS) and analyzed for cesium-137 by gamma-ray spectrometry. The isotopic composition of the radionuclides measured in BCR 482 suggests contributions from both global fallout resulting from historical nuclear weapons testing and more volatile materials released following the Chernobyl accident.

  5. Field-measured, hourly soil water evaporation stages in relation to reference evapotranspiration rate and soil to air temperature ratio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil water evaporation takes critical water supplies away from crops, especially in areas where both rainfall and irrigation water are limited. This study measured bare soil water evaporation from clay loam, silt loam, sandy loam, and fine sand soils. It found that on average almost half of the ir...

  6. Polychlorinated biphenyls (PCB), chlorinated pesticides, and polycyclic aromatic hydrocarbons (PAHs) in environmental standard reference materials

    SciTech Connect

    Poster, D.L.; Schantz, M.M.; Parris, R.M.; Benner, B.A. Jr.; Wise, S.A.

    1995-12-31

    Standard reference materials (SRMs) are certified reference materials issued by the National Institute of Standards and Technology (NIST). Natural matrix environmental sample SRMs have been developed the Analytical Chemistry Division to assist in validating measurements for organic contaminants in the environment. Many of these are well characterized for contaminants such as polychlorinated biphenyls (PCBs), chlorinated pesticides, and polycyclic aromatic hydrocarbons (PAHs). SRM 1649, Organics in Urban Dust, is currently available with certified concentrations for 5 PAHs but because of the widespread use of this material in air pollution monitoring programs and to expand the usefulness of this material, the authors are further characterizing the material for a larger number of PAHs as well as PCBs and chlorinated pesticides. They will also soon issue a diesel particulate extract (SRM 1975) that is well characterized for PAHS, including many nitrogen substituted compounds. In addition to natural matrix materials, solutions useful for calibrating chromatographic detector response factors and retention times, and spiking sample blanks for determination of analyte recoveries, are also available. Solution SRMs currently available contain PCS congeners, chlorinated pesticides, and PAHs. New solution SRMs in preparation will contain additional chlorinated pesticides, PCB congeners (e.g., non-ortho substituted chlorobiphenyls), and perdeuterated PAHs. Recent SRM work will be presented with particular attention on the methods used for determining organic contaminant concentrations in the urban dust material and in the diesel particulate extract.

  7. [Effects of Different Kinds of Organic Materials on Soil Heavy Metal Phytoremediation Efficiency by Sedum alfredii Hance].

    PubMed

    Yao, Gui-hua; Xu, Hai-zhou; Zhu, Lin-gang; Ma, Jia-wei; Liu, Dan; Ye, Zheng-qian

    2015-11-01

    In this study, a pot experiment was conducted to investigate the effect of clean organic materials i. e., biogas residue (BR), mushroom residue (MR), and bamboo shell (BS) on phytoextraction remediation of two heavy metal contaminated soils (collected from Wenzhou and Fuyang, which referred to "Wenzhou soil" and "Fuyang soil", respectively.) using a cadmium (Cd) and zinc (Zn) hyperaccumulator Sedum alfredii Hance. The results indicated that the effects of organic materials on availabilities of soil heavy metals were different due to different kinds of heavy metals, organic materials, and the application rates of the organic materials. Addition with 5% BR showed the greatest activation to copper (Cu), Zn in Wenzhou soil, and in Fuyang soil 1% BS had the highest activation for Cu, Zn, lead ( Ph) and Cd. Growth of shoot biomass of Sedum alfredii Hance increased with the addition rate of organic materials, and the plant dry weights were increased by 23.7%-93.0%. In Wenzhou soil, only 1% BS treatment had the best effect on Cd uptake and accumulation in shoots of Sedum alfredii Hance, increased by 22.6%, while other treatments were inferior to the control. For Zn, MR treatments were inferior to the control, while other treafments were superior to the control, of which 5% BR, 1% BS and 5% BS exceeded the control by 39. 6%, 32.6% and 23.8%, respectively. In Fuyang soil, for Cd, the treatment effects of 5% BS, 1% BR and 5% BR were the greatest, of which Cd accumulation in shoots exceeded the control by 12.9%, 12.8% and 6.2%, respectively, while Cd accumulations in shoots in all other treatments were less than that of control. For Zn, the treatments of adding organic materials promoted Zn accumulation in shoots of Sedum alfredii Hance, and the best treatments were as follows: 5% BS. 5% BR and 5% MR, exceeded the control by 38.4%, 25.7% and 22.4%, respectively.

  8. Microbiological destruction of composite polymeric materials in soils

    NASA Astrophysics Data System (ADS)

    Legonkova, O. A.; Selitskaya, O. V.

    2009-01-01

    Representatives of the same species of microscopic fungi developed on composite materials with similar polymeric matrices independently from the type of soils, in which the incubation was performed. Trichoderma harzianum, Penicillium auranthiogriseum, and Clonostachys solani were isolated from the samples of polyurethane. Fusarium solani, Clonostachys rosea, and Trichoderma harzianum predominated on the surface of ultrathene samples. Ulocladium botrytis, Penicillium auranthiogriseum, and Fusarium solani predominated in the variants with polyamide. Trichoderma harzianum, Penicillium chrysogenum, Aspergillus ochraceus, and Acremonium strictum were isolated from Lentex-based composite materials. Mucor circinelloides, Trichoderma harzianum, and Penicillium auranthiogriseum were isolated from composite materials based on polyvinyl alcohol. Electron microscopy demonstrated changes in the structure of polymer surface (loosening and an increase in porosity) under the impact of fungi. The physicochemical properties of polymers, including their strength, also changed. The following substances were identified as primary products of the destruction of composite materials: stearic acid for polyurethane-based materials; imide of dithiocarbonic acid and 1-nonadecen in variants with ultrathene; and tetraaminopyrimidine and isocyanatodecan in variants with polyamide. N,N-dimethyldodecan amide, 2-methyloximundecanon and 2-nonacosane were identified for composites on the base of Lentex A4-1. Allyl methyl sulfide and imide of dithiocarbonic acid were found in variants with the samples of composites based on polyvinyl alcohol. The identified primary products of the destruction of composite materials belong to nontoxic compounds.

  9. Present status and strategic plan for the stable isotope reference materials at the IAEA.

    NASA Astrophysics Data System (ADS)

    Assonov, Sergey; Groening, Manfred

    2016-04-01

    The presentation will give the overview of the stable isotope reference materials (SI-RMs) under distribution by the IAEA, its stable isotope laboratory and capacities related to material testing & production as well as future plans. Historically, most of the IAEA reference materials were produced and made available via collaborations with expert stable isotope laboratories worldwide. The IAEA plans include several directions as follows: • Maintaining the scale-defining SI-RMs at the highest level and introducing adequate replacements when needed; • Monitoring existing SI-RMs for any potential alteration(s) and of isotopic values assigned; • Identifying and then addressing the needs for new SI-RMs, with the priority to address the most critical applications (environmental and climate related applications, human health, food safety studies) and newly emerging analytical isotope techniques; • Performing all measurements aimed for characterisation of new SI-RMs and the corresponding uncertainty evaluation in accordance to the latest metrological concepts; • Promoting metrological approaches on traceability and uncertainty evaluation in every day practice of stable isotope measurements; • Expanding the IAEA capacities for SI-RMs by (i) planning a renewed laboratory at IAEA; (ii) enlarging collaboration with expert laboratories aimed to help IAEA in production and characterisation of new SI-RMs. These major directions will help to address the increasing demand for Stable Isotope Reference Materials.

  10. Development of candidate reference materials for the measurement of lead in bone

    PubMed Central

    Hetter, Katherine M.; Bellis, David J.; Geraghty, Ciaran; Todd, Andrew C.; Parsons, Patrick J.

    2010-01-01

    The production of modest quantities of candidate bone lead (Pb) reference materials is described, and an optimized production procedure is presented. The reference materials were developed to enable an assessment of the interlaboratory agreement of laboratories measuring Pb in bone; method validation; and for calibration of solid sampling techniques such as laser ablation ICP-MS. Long bones obtained from Pb-dosed and undosed animals were selected to produce four different pools of a candidate powdered bone reference material. The Pb concentrations of these pools reflect both environmental and occupational exposure levels in humans. The animal bones were harvested post mortem, cleaned, defatted, and broken into pieces using the brittle fracture technique at liquid nitrogen temperature. The bone pieces were then ground in a knife mill to produce fragments of 2-mm size. These were further ground in an ultra-centrifugal mill, resulting in finely powdered bone material that was homogenized and then sampled-scooped into vials. Testing for contamination and homogeneity was performed via instrumental methods of analysis. PMID:18421443

  11. Evaluation of new geological reference materials for uranium-series measurements: Chinese Geological Standard Glasses (CGSG) and macusanite obsidian.

    PubMed

    Denton, J S; Murrell, M T; Goldstein, S J; Nunn, A J; Amato, R S; Hinrichs, K A

    2013-10-15

    Recent advances in high-resolution, rapid, in situ microanalytical techniques present numerous opportunities for the analytical community, provided accurately characterized reference materials are available. Here, we present multicollector thermal ionization mass spectrometry (MC-TIMS) and multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) uranium and thorium concentration and isotopic data obtained by isotope dilution for a suite of newly available Chinese Geological Standard Glasses (CGSG) designed for microanalysis. These glasses exhibit a range of compositions including basalt, syenite, andesite, and a soil. Uranium concentrations for these glasses range from ∼2 to 14 μg g(-1), Th/U weight ratios range from ∼4 to 6, (234)U/(238)U activity ratios range from 0.93 to 1.02, and (230)Th/(238)U activity ratios range from 0.98 to 1.12. Uranium and thorium concentration and isotopic data are also presented for a rhyolitic obsidian from Macusani, SE Peru (macusanite). This glass can also be used as a rhyolitic reference material, has a very low Th/U weight ratio (around 0.077), and is approximately in (238)U-(234)U-(230)Th secular equilibrium. The U-Th concentration data agree with but are significantly more precise than those previously measured. U-Th concentration and isotopic data agree within estimated errors for the two measurement techniques, providing validation of the two methods. The large (238)U-(234)U-(230)Th disequilibria for some of the glasses, along with the wide range in their chemical compositions and Th/U ratios should provide useful reference points for the U-series analytical community. PMID:24004454

  12. Evaluation of new geological reference materials for uranium-series measurements: Chinese Geological Standard Glasses (CGSG) and macusanite obsidian.

    PubMed

    Denton, J S; Murrell, M T; Goldstein, S J; Nunn, A J; Amato, R S; Hinrichs, K A

    2013-10-15

    Recent advances in high-resolution, rapid, in situ microanalytical techniques present numerous opportunities for the analytical community, provided accurately characterized reference materials are available. Here, we present multicollector thermal ionization mass spectrometry (MC-TIMS) and multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) uranium and thorium concentration and isotopic data obtained by isotope dilution for a suite of newly available Chinese Geological Standard Glasses (CGSG) designed for microanalysis. These glasses exhibit a range of compositions including basalt, syenite, andesite, and a soil. Uranium concentrations for these glasses range from ∼2 to 14 μg g(-1), Th/U weight ratios range from ∼4 to 6, (234)U/(238)U activity ratios range from 0.93 to 1.02, and (230)Th/(238)U activity ratios range from 0.98 to 1.12. Uranium and thorium concentration and isotopic data are also presented for a rhyolitic obsidian from Macusani, SE Peru (macusanite). This glass can also be used as a rhyolitic reference material, has a very low Th/U weight ratio (around 0.077), and is approximately in (238)U-(234)U-(230)Th secular equilibrium. The U-Th concentration data agree with but are significantly more precise than those previously measured. U-Th concentration and isotopic data agree within estimated errors for the two measurement techniques, providing validation of the two methods. The large (238)U-(234)U-(230)Th disequilibria for some of the glasses, along with the wide range in their chemical compositions and Th/U ratios should provide useful reference points for the U-series analytical community.

  13. Comparing results from two continental geochemical surveys to world soil composition and deriving Predicted Empirical Global Soil (PEGS2) reference values

    NASA Astrophysics Data System (ADS)

    de Caritat, Patrice; Reimann, Clemens; Bastrakov, E.; Bowbridge, D.; Boyle, P.; Briggs, S.; Brown, D.; Brown, M.; Brownlie, K.; Burrows, P.; Burton, G.; Byass, J.; de Caritat, P.; Chanthapanya, N.; Cooper, M.; Cranfield, L.; Curtis, S.; Denaro, T.; Dhnaram, C.; Dhu, T.; Diprose, G.; Fabris, A.; Fairclough, M.; Fanning, S.; Fidler, R.; Fitzell, M.; Flitcroft, P.; Fricke, C.; Fulton, D.; Furlonger, J.; Gordon, G.; Green, A.; Green, G.; Greenfield, J.; Harley, J.; Heawood, S.; Hegvold, T.; Henderson, K.; House, E.; Husain, Z.; Krsteska, B.; Lam, J.; Langford, R.; Lavigne, T.; Linehan, B.; Livingstone, M.; Lukss, A.; Maier, R.; Makuei, A.; McCabe, L.; McDonald, P.; McIlroy, D.; McIntyre, D.; Morris, P.; O'Connell, G.; Pappas, B.; Parsons, J.; Petrick, C.; Poignand, B.; Roberts, R.; Ryle, J.; Seymon, A.; Sherry, K.; Skinner, J.; Smith, M.; Strickland, C.; Sutton, S.; Swindell, R.; Tait, H.; Tang, J.; Thomson, A.; Thun, C.; Uppill, B.; Wall, K.; Watkins, J.; Watson, T.; Webber, L.; Whiting, A.; Wilford, J.; Wilson, T.; Wygralak, A.; Albanese, S.; Andersson, M.; Arnoldussen, A.; Baritz, R.; Batista, M. J.; Bel-lan, A.; Birke, M.; Cicchella, C.; Demetriades, A.; Dinelli, E.; De Vivo, B.; De Vos, W.; Duris, M.; Dusza-Dobek, A.; Eggen, O. A.; Eklund, M.; Ernstsen, V.; Filzmoser, P.; Finne, T. E.; Flight, D.; Forrester, S.; Fuchs, M.; Fugedi, U.; Gilucis, A.; Gosar, M.; Gregorauskiene, V.; Gulan, A.; Halamić, J.; Haslinger, E.; Hayoz, P.; Hobiger, G.; Hoffmann, R.; Hoogewerff, J.; Hrvatovic, H.; Husnjak, S.; Janik, L.; Johnson, C. C.; Jordan, G.; Kirby, J.; Kivisilla, J.; Klos, V.; Krone, F.; Kwecko, P.; Kuti, L.; Ladenberger, A.; Lima, A.; Locutura, J.; Lucivjansky, P.; Mackovych, D.; Malyuk, B. I.; Maquil, R.; McLaughlin, M.; Meuli, R. G.; Miosic, N.; Mol, G.; Négrel, P.; O'Connor, P.; Oorts, K.; Ottesen, R. T.; Pasieczna, A.; Petersell, V.; Pfleiderer, S.; Poňavič, M.; Prazeres, C.; Rauch, U.; Reimann, C.; Salpeteur, I.; Schedl, A.; Scheib, A.; Schoeters, I.; Sefcik, P.; Sellersjö, E.; Skopljak, F.; Slaninka, I.; Šorša, A.; Srvkota, R.; Stafilov, T.; Tarvainen, T.; Trendavilov, V.; Valera, P.; Verougstraete, V.; Vidojević, D.; Zissimos, A. M.; Zomeni, Z.

    2012-02-01

    Analytical data for 10 major oxides (Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O, P2O5, SiO2 and TiO2), 16 total trace elements (As, Ba, Ce, Co, Cr, Ga, Nb, Ni, Pb, Rb, Sr, Th, V, Y, Zn and Zr), 14 aqua regia extracted elements (Ag, As, Bi, Cd, Ce, Co, Cs, Cu, Fe, La, Li, Mn, Mo and Pb), Loss On Ignition (LOI) and pH from 3526 soil samples from two continents (Australia and Europe) are presented and compared to (1) the composition of the upper continental crust, (2) published world soil average values, and (3) data from other continental-scale soil surveys. It can be demonstrated that average upper continental crust values do not provide reliable estimates for natural concentrations of elements in soils. For many elements there exist substantial differences between published world soil averages and the median concentrations observed on two continents. Direct comparison with other continental datasets is hampered by the fact that often mean, instead of the statistically more robust median, is reported. Using a database of the worldwide distribution of lithological units, it can be demonstrated that lithology is a poor predictor of soil chemistry. Climate-related processes such as glaciation and weathering are strong modifiers of the geochemical signature inherited from bedrock during pedogenesis. To overcome existing shortcomings of predicted global or world soil geochemical reference values, we propose Preliminary Empirical Global Soil reference values based on analytical results of a representative number of soil samples from two continents (PEGS2).

  14. Development of green onion and cabbage certified reference materials for quantification of organophosphorus and pyrethroid pesticides.

    PubMed

    Otake, Takamitsu; Yarita, Takashi; Aoyagi, Yoshie; Kuroda, Youko; Numata, Masahiko; Iwata, Hitoshi; Mizukoshi, Kazushi; Nakamura, Munetomo; Watai, Masatoshi; Mitsuda, Hitoshi; Fujikawa, Takashi; Ota, Hidekazu

    2011-08-24

    Green onion and cabbage certified reference materials for the analysis of pesticide residues were issued by the National Metrology Institute of Japan, part of the National Institute of Advanced Industrial Science and Technology. Green onion and cabbage samples were grown so as to contain several kinds of organophosphorus and pyrethroid pesticides, and those were collected from a field in the Kochi Prefecture in Japan. The certification was carried out by using multiple analytical methods to ensure the reliability of analytical results; the values of target pesticides (diazinon, fenitrothion, cypermethrin, etofenprox, and permethrin for green onion and chlorpyrifos, fenitrothion, and permethrin for cabbage) were obtained by isotope dilution mass spectrometry. Certified values of target pesticides were 0.96-13.9 and 2.41-6.9 mg/kg for green onion and cabbage, respectively. These are the first green onion and cabbage powder certified reference materials in which organophosphorus and pyrethroid pesticides are determined. PMID:21774469

  15. Reference Materials for Calibration of Analytical Biases in Quantification of DNA Methylation.

    PubMed

    Yu, Hannah; Hahn, Yoonsoo; Yang, Inchul

    2015-01-01

    Most contemporary methods for the quantification of DNA methylation employ bisulfite conversion and PCR amplification. However, many reports have indicated that bisulfite-mediated PCR methodologies can result in inaccurate measurements of DNA methylation owing to amplification biases. To calibrate analytical biases in quantification of gene methylation, especially those that arise during PCR, we utilized reference materials that represent exact bisulfite-converted sequences with 0% and 100% methylation status of specific genes. After determining relative quantities using qPCR, pairs of plasmids were gravimetrically mixed to generate working standards with predefined DNA methylation levels at 10% intervals in terms of mole fractions. The working standards were used as controls to optimize the experimental conditions and also as calibration standards in melting-based and sequencing-based analyses of DNA methylation. Use of the reference materials enabled precise characterization and proper calibration of various biases during PCR and subsequent methylation measurement processes, resulting in accurate measurements. PMID:26368560

  16. Prompt gamma activation analysis of boron in reference materials using diffracted polychromatic neutron beam

    NASA Astrophysics Data System (ADS)

    Byun, S. H.; Sun, G. M.; Choi, H. D.

    2004-01-01

    Boron concentrations were analyzed for standard reference materials by prompt gamma activation analysis (PGAA). The measurements were performed at the SNU-KAERI PGAA facility installed at Hanaro, the research reactor of Korea Atomic Energy Research Institute (KAERI). The facility uses a diffracted polychromatic beam with a neutron flux of 7.9 × 10 7 n/cm 2 s. Elemental sensitivity for boron was calibrated from the prompt gamma-ray spectra of boric acid samples containing 2-45 μg boron. The sensitivity of 2131 cps/mg-B was obtained from the linearity of the boron peak count rate versus the boron mass. The detection limit for boron was estimated to be 67 ng from an empty sample bag spectrum for a counting time of 10,000 s. The measured boron concentrations for standard reference materials showed good consistency with the certified or information values.

  17. Aflatoxin B1 in peanut meal reference materials: intercomparisons of methods.

    PubMed

    Van Egmond, H P; Wagstaffe, P J

    1989-01-01

    The Community Bureau of Reference (BCR) is preparing a series of animal feed reference materials to provide a basis for analytical quality assurance for aflatoxin B1 analysis, a problem of particular importance in view of Community legislation. Before reference values can be assigned to the reference materials the major errors in the underlying measurements must be identified and reduced. This paper presents the results of two intercomparison exercises involving some 20 European laboratories who applied a wide variety of analytical methods. It is shown that the major source of error and discrepancy is connected with incomplete extraction and/or losses during clean-up and that, provided correction for recovery/background interference is made, many methods can achieve acceptable accuracy. Sources of error and their control are discussed, and essential details of the methods used are presented. It is concluded that analytical QA is more important than the use of standardized methods when a high degree of accuracy and comparability are required. PMID:2498137

  18. Metrological approaches to organic chemical purity: primary reference materials for vitamin D metabolites.

    PubMed

    Nelson, Michael A; Bedner, Mary; Lang, Brian E; Toman, Blaza; Lippa, Katrice A

    2015-11-01

    Given the critical role of pure, organic compound primary reference standards used to characterize and certify chemical Certified Reference Materials (CRMs), it is essential that associated mass purity assessments be fit-for-purpose, represented by an appropriate uncertainty interval, and metrologically sound. The mass fraction purities (% g/g) of 25-hydroxyvitamin D (25(OH)D) reference standards used to produce and certify values for clinical vitamin D metabolite CRMs were investigated by multiple orthogonal quantitative measurement techniques. Quantitative (1)H-nuclear magnetic resonance spectroscopy (qNMR) was performed to establish traceability of these materials to the International System of Units (SI) and to directly assess the principal analyte species. The 25(OH)D standards contained volatile and water impurities, as well as structurally-related impurities that are difficult to observe by chromatographic methods or to distinguish from the principal 25(OH)D species by one-dimensional NMR. These impurities have the potential to introduce significant biases to purity investigations in which a limited number of measurands are quantified. Combining complementary information from multiple analytical methods, using both direct and indirect measurement techniques, enabled mitigation of these biases. Purities of 25(OH)D reference standards and associated uncertainties were determined using frequentist and Bayesian statistical models to combine data acquired via qNMR, liquid chromatography with UV absorbance and atmospheric pressure-chemical ionization mass spectrometric detection (LC-UV, LC-ACPI-MS), thermogravimetric analysis (TGA), and Karl Fischer (KF) titration.

  19. Processing lunar soils for oxygen and other materials

    NASA Technical Reports Server (NTRS)

    Knudsen, Christian W.; Gibson, Michael A.

    1992-01-01

    Two types of lunar materials are excellent candidates for lunar oxygen production: ilmenite and silicates such as anorthite. Both are lunar surface minable, occurring in soils, breccias, and basalts. Because silicates are considerably more abundant than ilmenite, they may be preferred as source materials. Depending on the processing method chosen for oxygen production and the feedstock material, various useful metals and bulk materials can be produced as byproducts. Available processing techniques include hydrogen reduction of ilmenite and electrochemical and chemical reductions of silicates. Processes in these categories are generally in preliminary development stages and need significant research and development support to carry them to practical deployment, particularly as a lunar-based operation. The goal of beginning lunar processing operations by 2010 requires that planning and research and development emphasize the simplest processing schemes. However, more complex schemes that now appear to present difficult technical challenges may offer more valuable metal byproducts later. While they require more time and effort to perfect, the more complex or difficult schemes may provide important processing and product improvements with which to extend and elaborate the initial lunar processing facilities. A balanced R&D program should take this into account. The following topics are discussed: (1) ilmenite--semi-continuous process; (2) ilmenite--continuous fluid-bed reduction; (3) utilization of spent ilmenite to produce bulk materials; (4) silicates--electrochemical reduction; and (5) silicates--chemical reduction.

  20. Transformation of paralytic shellfish poisoning toxins in Crassostrea gigas and Pecten maximus reference materials.

    PubMed

    Turner, Andrew D; Lewis, Adam M; Hatfield, Robert G; Galloway, Angus W; Higman, Wendy A

    2012-11-01

    Matrix reference materials are an important requirement for the assessment of method performance characteristics and for routine quality control. In the field of marine toxin testing where biological assays have been used and where modern analytical testing methods are now becoming available, this requirement has become an urgent one. Various approaches are utilised for preparation of such materials in the absence of available naturally occurring toxic shellfish samples. Toxin-free shellfish may be artificially fortified through the addition of cultured toxic phytoplankton or shellfish may be incurred through natural feeding on toxic algae in a laboratory environment. Both of these approaches may be potentially affected by issues relating to the degradation or transformation of toxin analytes, so studies were conducted to assess these effects within our laboratory. A range of PSP-toxic shellfish tissues were prepared using the two approaches, in both Pacific oyster (Crassostrea gigas) and king scallops (Pecten maximus). Additionally, sub-samples of incurred Pacific oyster tissue were further treated, through addition of artificial chemical stabilisers and gamma irradiation. Two separate month-long stability trials were conducted at +4 °C on each material. Results highlighted clear evidence for improved stability of materials following shellfish feeding experiments in comparison with the tissues which had been spiked with plankton. In addition, there were clear differences in stability of toxins between the two shellfish species studied. There was evidence for good stability of C1&2 toxins in both the incurred tissues and improved stability of some toxins in tissues which had been subjected to either gamma irradiation or treatment with chemical additives. The results therefore highlighted the benefits of conducting shellfish feeding if suitable stable reference materials are to be prepared containing a full range of PSP toxin analytes. The study also highlighted

  1. Determination of elements in National Bureau of Standards' geological Standard Reference Materials by neutron activation analysis

    SciTech Connect

    Graham, C.C.; Glascock, M.D.; Carni, J.J.; Vogt, J.R.; Spalding, T.G.

    1982-08-01

    Instrumental neutron activation analysis (INAA) and prompt gamma neutron activation analysis (PGNAA) have been used to determine elemental concentrations in two recently issued National Bureau of Standards (NBS) Standard Reference Materials (SRM's). The results obtained are in good agreement with the certified and information values reported by NBS for those elements in each material for which comparisons are available. Average concentrations of 35 elements in SRM 278 obsidian rock and 32 elements in SRM 688 basalt rock are reported for comparison with results that may be obtained by other laboratories.

  2. Novel application of high pressure processing for the production of shellfish toxin matrix reference materials.

    PubMed

    Turner, Andrew D; Powell, Andy L; Burrell, Stephen

    2014-11-01

    The production of homogeneous and stable matrix reference materials for marine biotoxins is important for the validation and implementation of instrumental methods of analysis. High pressure processing was investigated to ascertain potential advantages this technique may have in stabilising paralytic shellfish poisoning toxins in shellfish tissues compared to untreated materials. Oyster tissues were subjected to a range of different temperatures and pressures, with results showing a significant reduction in biological activity in comparison to control samples, without significantly altering toxin profiles. Tissue subjected to pressures >600 MPa at 50 °C was assessed for homogeneity and stability. The sample homogeneity was determined using a pre-column oxidation LC-FLD method and shown to be within accepted levels of within batch repeatability. Short and long-term stability studies were conducted over a range of temperatures, with analysis by pre and post column oxidation LC-FLD demonstrating improved stability of toxins compared to the untreated materials and with epimerisation of toxins also notably reduced in treated materials. This study confirmed the technique of high pressure processing to improve the stability of PSP toxins compared to untreated wet tissues and highlighted its applicability in reference material preparation where removal of biological activity is of importance.

  3. Novel application of high pressure processing for the production of shellfish toxin matrix reference materials.

    PubMed

    Turner, Andrew D; Powell, Andy L; Burrell, Stephen

    2014-11-01

    The production of homogeneous and stable matrix reference materials for marine biotoxins is important for the validation and implementation of instrumental methods of analysis. High pressure processing was investigated to ascertain potential advantages this technique may have in stabilising paralytic shellfish poisoning toxins in shellfish tissues compared to untreated materials. Oyster tissues were subjected to a range of different temperatures and pressures, with results showing a significant reduction in biological activity in comparison to control samples, without significantly altering toxin profiles. Tissue subjected to pressures >600 MPa at 50 °C was assessed for homogeneity and stability. The sample homogeneity was determined using a pre-column oxidation LC-FLD method and shown to be within accepted levels of within batch repeatability. Short and long-term stability studies were conducted over a range of temperatures, with analysis by pre and post column oxidation LC-FLD demonstrating improved stability of toxins compared to the untreated materials and with epimerisation of toxins also notably reduced in treated materials. This study confirmed the technique of high pressure processing to improve the stability of PSP toxins compared to untreated wet tissues and highlighted its applicability in reference material preparation where removal of biological activity is of importance. PMID:25086341

  4. The role of adequate reference materials in density measurements in hemodialysis

    NASA Astrophysics Data System (ADS)

    Furtado, A.; Moutinho, J.; Moura, S.; Oliveira, F.; Filipe, E.

    2015-02-01

    In hemodialysis, oscillation-type density meters are used to measure the density of the acid component of the dialysate solutions used in the treatment of kidney patients. An incorrect density determination of this solution used in hemodialysis treatments can cause several and adverse events to patients. Therefore, despite the Fresenius Medical Care (FME) tight control of the density meters calibration results, this study shows the benefits of mimic the matrix usually measured to produce suitable reference materials for the density meter calibrations.

  5. Development of benzene, toluene, ethylbenzene and xylenes certified gaseous reference materials

    NASA Astrophysics Data System (ADS)

    Brum, M. C.; Sobrinho, D. C. G.; Fagundes, F. A.; Oudwater, R. J.; Augusto, C. R.

    2016-07-01

    The work describes the production of certified gaseous reference materials of benzene, toluene, ethylbenzene and xylenes (BTEX) in nitrogen from the gravimetric production up to the long term stability tests followed by the certifying step. The uncertainty in the amount fractions of the compounds in these mixtures was approximately 4% (relative) for the range studied from 2 to 16 µmol/mol. Also the adsorption of the BTEX on the cylinder surface and the tubing were investigated as potential uncertainty source.

  6. Compositional analysis of biomass reference materials: Results from an interlaboratory study

    SciTech Connect

    Templeton, David W.; Wolfrum, Edward J.; Yen, James H.; Sharpless, Katherine E.

    2015-10-29

    Biomass compositional methods are used to compare different lignocellulosic feedstocks, to measure component balances around unit operations and to determine process yields and therefore the economic viability of biomass-to-biofuel processes. Four biomass reference materials (RMs NIST 8491–8494) were prepared and characterized, via an interlaboratory comparison exercise in the early 1990s to evaluate biomass summative compositional methods, analysts, and laboratories. Having common, uniform, and stable biomass reference materials gives the opportunity to assess compositional data compared to other analysts, to other labs, and to a known compositional value. The expiration date for the original characterization of these RMs was reached and an effort to assess their stability and recharacterize the reference values for the remaining material using more current methods of analysis was initiated. We sent samples of the four biomass RMs to 11 academic, industrial, and government laboratories, familiar with sulfuric acid compositional methods, for recharacterization of the component reference values. In this work, we have used an expanded suite of analytical methods that are more appropriate for herbaceous feedstocks, to recharacterize the RMs’ compositions. We report the median values and the expanded uncertainty values for the four RMs on a dry-mass, whole-biomass basis. The original characterization data has been recalculated using median statistics to facilitate comparisons with this data. We found improved total component closures for three out of the four RMs compared to the original characterization, and the total component closures were near 100 %, which suggests that most components were accurately measured and little double counting occurred. Here, the major components were not statistically different in the recharacterization which suggests that the biomass materials are stable during storage and that additional components, not seen in the original

  7. Compositional analysis of biomass reference materials: Results from an interlaboratory study

    DOE PAGES

    Templeton, David W.; Wolfrum, Edward J.; Yen, James H.; Sharpless, Katherine E.

    2015-10-29

    Biomass compositional methods are used to compare different lignocellulosic feedstocks, to measure component balances around unit operations and to determine process yields and therefore the economic viability of biomass-to-biofuel processes. Four biomass reference materials (RMs NIST 8491–8494) were prepared and characterized, via an interlaboratory comparison exercise in the early 1990s to evaluate biomass summative compositional methods, analysts, and laboratories. Having common, uniform, and stable biomass reference materials gives the opportunity to assess compositional data compared to other analysts, to other labs, and to a known compositional value. The expiration date for the original characterization of these RMs was reached andmore » an effort to assess their stability and recharacterize the reference values for the remaining material using more current methods of analysis was initiated. We sent samples of the four biomass RMs to 11 academic, industrial, and government laboratories, familiar with sulfuric acid compositional methods, for recharacterization of the component reference values. In this work, we have used an expanded suite of analytical methods that are more appropriate for herbaceous feedstocks, to recharacterize the RMs’ compositions. We report the median values and the expanded uncertainty values for the four RMs on a dry-mass, whole-biomass basis. The original characterization data has been recalculated using median statistics to facilitate comparisons with this data. We found improved total component closures for three out of the four RMs compared to the original characterization, and the total component closures were near 100 %, which suggests that most components were accurately measured and little double counting occurred. Here, the major components were not statistically different in the recharacterization which suggests that the biomass materials are stable during storage and that additional components, not seen in the original

  8. Software Management Environment (SME) release 9.4 user reference material

    NASA Technical Reports Server (NTRS)

    Hendrick, R.; Kistler, D.; Manter, K.

    1992-01-01

    This document contains user reference material for the Software Management Environment (SME) prototype, developed for the Systems Development Branch (Code 552) of the Flight Dynamics Division (FDD) of Goddard Space Flight Center (GSFC). The SME provides an integrated set of management tools that can be used by software development managers in their day-to-day management and planning activities. This document provides an overview of the SME, a description of all functions, and detailed instructions concerning the software's installation and use.

  9. Compositional Analysis of Biomass Reference Materials: Results from an Interlaboratory Study

    PubMed Central

    Wolfrum, Edward J.; Yen, James H.; Sharpless, Katherine E.

    2016-01-01

    Biomass compositional methods are used to compare different lignocellulosic feedstocks, to measure component balances around unit operations and to determine process yields and therefore the economic viability of biomass-to-biofuel processes. Four biomass reference materials (RMs NIST 8491–8494) were prepared and characterized, via an interlaboratory comparison exercise in the early 1990s to evaluate biomass summative compositional methods, analysts, and laboratories. Having common, uniform, and stable biomass reference materials gives the opportunity to assess compositional data compared to other analysts, to other labs, and to a known compositional value. The expiration date for the original characterization of these RMs was reached and an effort to assess their stability and recharacterize the reference values for the remaining material using more current methods of analysis was initiated. We sent samples of the four biomass RMs to 11 academic, industrial, and government laboratories, familiar with sulfuric acid compositional methods, for recharacterization of the component reference values. In this work, we have used an expanded suite of analytical methods that are more appropriate for herbaceous feedstocks, to recharacterize the RMs’ compositions. We report the median values and the expanded uncertainty values for the four RMs on a dry-mass, whole-biomass basis. The original characterization data has been recalculated using median statistics to facilitate comparisons with this data. We found improved total component closures for three out of the four RMs compared to the original characterization, and the total component closures were near 100 %, which suggests that most components were accurately measured and little double counting occurred. The major components were not statistically different in the recharacterization which suggests that the biomass materials are stable during storage and that additional components, not seen in the original

  10. Adiabatic Calorimetry as Support to the Certification of High-Purity Liquid Reference Materials

    NASA Astrophysics Data System (ADS)

    Baldan, A.; Bosma, R.; Peruzzi, A.; van der Veen, A. M. H.; Shimizu, Y.

    2009-02-01

    The certification of high-purity liquid reference materials is supported by several analytical techniques (e.g., gas chromatography, liquid chromatography, Karl Fischer coulometry, inductively coupled plasma mass spectrometry, differential scanning calorimetry, adiabatic calorimetry). Most of them provide information on a limited set of specific impurities present in the sample (indirect methods). Adiabatic calorimetry [1] complementarily provides the overall molar fraction of impurities with sensitivity down to few μmol · mol-1 without giving any information about the nature of the impurities present in the sample (direct method). As the combination of adiabatic calorimetry with one (or more than one) indirect chemical techniques was regarded as an optimal methodology, NMi VSL developed an adiabatic calorimetry facility for the purity determination of high-purity liquid reference materials [2]. Within the framework of collaboration with NMIJ, a benzene-certified reference material (NMIJ CRM 4002) from NMIJ was analyzed by adiabatic calorimetry at NMi VSL. The results of this measurement are reported in this paper. Good agreement with the NMIJ-certified purity value (99.992 ± 0.003) cmol · mol-1 was found. The influence of different data analysis approaches (e.g., extrapolation functions, melting ranges) on the measurement results is reported. The uncertainty of the measured purity was estimated.

  11. Small-Angle Neutron Scattering study of the NIST mAb reference material

    NASA Astrophysics Data System (ADS)

    Castellanos, Maria Monica; Liu, Yun; Krueger, Susan; Curtis, Joseph

    Monoclonal antibodies (mAbs) are of great interest to the biopharmaceutical industry because they can be engineered to target specific antigens. Due to their importance, the biomanufacturing initiative at NIST is developing an IgG1 mAb reference material `NIST mAb', which can be used by industry, academia, and regulatory authorities. As part of this collaborative effort, we aim at characterizing the reference material using neutron scattering techniques. We have studied the small-angle scattering profile of the NIST mAb in a histidine buffer at 0 and 150 mM NaCl. Using Monte Carlo simulations, we generate an ensemble of structures and calculate their theoretical scattering profile, which can be directly compared with experimental data. Moreover, we analyze the structure factor to understand the effect of solution conditions on the protein-protein interactions. Finally, we have measured the solution scattering of the NIST mAb, while simultaneously performing freeze/thaw cycles, in order to investigate if the solution structure was affected upon freezing. The results from neutron scattering not only support the development of the reference material, but also provide insights on its stability and guide efforts for its development under different formulations.

  12. A CBNM 6Li spike isotopic reference material CBNM-IRM-615

    NASA Astrophysics Data System (ADS)

    Lamberty, A.; Verbruggen, A.; Hendrickx, F.; de Bièvre, P.

    1992-04-01

    A 6Li spike isotopic reference material CBNM-IRM-615 has been prepared in the form of Li2CO3 in HCl. The lithium concentration, (4.001 ± 0.028) × 10-3 mol Li kg-1, was determined by isotope dilution mass spectrometry against NBS SRM 924 Li2CO3. CBNM-IRM-615 is certified for its isotopic composition: 95.610 ± 0.025 amount % 6Li; 4.390 ± 0.025 amount % 7Li; and for its 6Li concentration: 3.825 ± 0.027 × 10-3 mol 6Li kg-1 of solution. Uncertainties are 2s or the equivalent estimate thereof. The isotopic reference material is available in quartz ampoules containing approximately 5 g of solution. Using this spike isotopic reference material. 7Li or total Li concentrations in unknown samples can be determined by isotope dilution mass spectrometry via a measurement of the molar isotope dilution ratio RB = 6Li/7Li in the blend.

  13. Soil solid materials affect the kinetics of extracellular enzymatic reactions

    NASA Astrophysics Data System (ADS)

    Lammirato, C.; Miltner, A.; Kästner, M.

    2009-04-01

    INTRODUCTION Soil solid materials affect the degradation processes of many organic compounds by decreasing the bioavailability of substrates and by interacting with degraders. The magnitude of this effect in the environment is shown by the fact that xenobiotics which are readily metabolized in aquatic environments can have long residence times in soil. Extracellular enzymatic hydrolysis of cellobiose (enzyme: beta-glucosidase from Aspergillus niger) was chosen as model degradation process since it is easier to control and more reproducible than a whole cell processes. Furthermore extracellular enzymes play an important role in the environment since they are responsible for the first steps in the degradation of organic macromolecules; beta-glucosidase is key enzyme in the degradation of cellulose and therefore it is fundamental in the carbon cycle and for soil in general. The aims of the project are: 1) quantification of solid material effect on degradation, 2) separation of the effects of minerals on enzyme (adsorption →change in activity) and substrate (adsorption →change in bioavailability). Our hypothesis is that a rate reduction in the enzymatic reaction in the presence of a solid phase results from the sum of decreased bioavailability of the substrate and decreased activity of enzyme molecules. The relative contribution of the two terms to the overall effect can vary widely depending on the chemical nature of the substrate, the properties of the enzyme and on the surface properties of the solid materials. Furthermore we hypothesize that by immobilizing the enzyme in an appropriate carrier the adsorption of enzymes to soil materials can be eliminated and that therefore immobilization can increase the overall reaction rate (activity loss caused by immobilization < activity loss caused by adsorption to soil minerals). MATERIALS AND METHODS Enzymatic kinetic experiments are carried out in homogeneous liquid systems and in heterogeneous systems where solid

  14. Characterization of Pu concentration and its isotopic composition in a reference fallout material.

    PubMed

    Zhang, Yongsan; Zheng, Jian; Yamada, Masatoshi; Wu, Fengchang; Igarashi, Yasuhito; Hirose, Katsumi

    2010-02-01

    Because there is no reference material for fallout plutonium isotope monitoring, preparation of such a material is necessary for quality control of fallout radionuclides analysis for atmospheric environmental studies. In this work, we report the characterization of Pu activity and its isotopic composition in a reference fallout material prepared by the Meteorological Research Institute (MRI), Japan. This material was prepared from samples collected at 14 stations throughout Japan in 1963-1979, with reference values of (137)Cs, (90)Sr and (239)(+)(240)Pu activities. We analyzed the activities of (239)(+)(240)Pu and (241)Pu, and the atom ratios of (240)Pu/(239)Pu and (241)Pu/(239)Pu using an isotope dilution sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS). The (239)(+)(240)Pu activities in this fallout material using acid leaching and total digestion were 6.56+/-0.20 mBq/g and 6.79+/-0.16 mBq/g, respectively. Atom ratios of (240)Pu/(239)Pu were 0.1915+/-0.0030 and 0.1922+/-0.0044, respectively. Both (240)Pu/(239)Pu and (241)Pu/(239)Pu atom ratios were slightly higher than those of global fallout, which could be attributed to the deposition of fallout radionuclides resulting from the Chinese nuclear weapons tests conducted in the 1970s. The dominant host phases of (239)(+)(240)Pu were found to be organic matter-sulfides (70%) with a relative high (240)Pu/(239)Pu atom ratio, and Fe-Mn oxides (19%) using a sequential extraction method.

  15. Dynamic soil property reference values and soil resilience: Keys to developing innovative, sustainable solutions for American agriculture?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers, ranchers, conservationists and other land managers can benefit from four types of soil information when developing new management systems and deciding where to apply currently available systems: (1) values for relatively static soil properties and relationships to plant growth, (2) values f...

  16. Inter-laboratory variation in the chemical analysis of acidic forest soil reference samples from eastern North America

    USGS Publications Warehouse

    Ross, Donald S.; Bailiey, Scott W; Briggs, Russell D; Curry, Johanna; Fernandez, Ivan J.; Fredriksen, Guinevere; Goodale, Christine L.; Hazlett, Paul W.; Heine, Paul R; Johnson, Chris E.; Larson, John T; Lawrence, Gregory B.; Kolka, Randy K; Ouimet, Rock; Pare, D; Richter, Daniel D.; Shirmer, Charles D; Warby, Richard A.F.

    2015-01-01

    Long-term forest soil monitoring and research often requires a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from agronomic and horticultural soils. Soil proficiency programs do not generally include forest soil samples that are highly acidic, high in extractable Al, low in extractable Ca and often high in carbon. To determine the uncertainty associated with specific analytical methods for forest soils, we collected and distributed samples from two soil horizons (Oa and Bs) to 15 laboratories in the eastern United States and Canada. Soil properties measured included total organic carbon and nitrogen, pH and exchangeable cations. Overall, results were consistent despite some differences in methodology. We calculated the median absolute deviation (MAD) for each measurement and considered the acceptable range to be the median 6 2.5 3 MAD. Variability among laboratories was usually as low as the typical variability within a laboratory. A few areas of concern include a lack of consistency in the measurement and expression of results on a dry weight basis, relatively high variability in the C/N ratio in the Bs horizon, challenges associated with determining exchangeable cations at concentrations near the lower reporting range of some laboratories and the operationally defined nature of aluminum extractability. Recommendations include a continuation of reference forest soil exchange programs to quantify the uncertainty associated with these analyses in conjunction with ongoing efforts to review and standardize laboratory methods.

  17. Exploration of optical fibres as a carrier for new benzene and toluene matrix-free reference materials.

    PubMed

    Słomińska, Marta; Marć, Mariusz; Szczygelska-Tao, Jolanta; Konieczka, Piotr; Namieśnik, Jacek

    2015-07-01

    To meet high expectations concerning precision and accuracy of reference materials, preparation of matrix-free reference materials using thermal decomposition-gas chromatography-mass spectrometry (TD-GC-MS) was proposed in this study. In the paper, the results obtained in preparation of the new reference materials for benzene and toluene are presented, based on the thermal decomposition technique of compounds chemically bound to the surface of optical fibre segments. The results obtained at various stages of the research procedure (homogeneity, stability) confirmed the possibility of using prepared laboratory samples of materials as reference materials for benzene and toluene. For the prepared batch of materials, reference values 1.26 ± 0.91 (ng/fibre) for benzene and 11.3 ± 7.4 (ng/fibre) for toluene were determined.

  18. Development of a certified reference material for genetically modified potato with altered starch composition.

    PubMed

    Broothaerts, Wim; Corbisier, Philippe; Emons, Hendrik; Emteborg, Håkan; Linsinger, Thomas P J; Trapmann, Stefanie

    2007-06-13

    The presence of genetically modified organisms (GMOs) in food and feed products is subject to regulation in the European Union (EU) and elsewhere. As part of the EU authorization procedure for GMOs intended for food and feed use, reference materials must be produced for the quality control of measurements to quantify the GMOs. Certified reference materials (CRMs) are available for a range of herbicide- and insect-resistant genetically modified crops such as corn, soybean, and cotton. Here the development of the first CRM for a GMO that differs from its non-GMO counterpart in a major compositional constituent, that is, starch, is described. It is shown that the modification of the starch composition of potato (Solanum tuberosum L.) tubers, together with other characteristics of the delivered materials, have important consequences for the certification strategy. Moreover, the processing and characterization of the EH92-527-1 potato material required both new and modified procedures, different from those used routinely for CRMs produced from genetically modified seeds. PMID:17508757

  19. Validation of reference materials for uranium radiochronometry in the frame of nuclear forensic investigations.

    PubMed

    Varga, Z; Mayer, K; Bonamici, C E; Hubert, A; Hutcheon, I; Kinman, W; Kristo, M; Pointurier, F; Spencer, K; Stanley, F; Steiner, R; Tandon, L; Williams, R

    2015-08-01

    The results of a joint effort by expert nuclear forensic laboratories in the area of age dating of uranium, i.e. the elapsed time since the last chemical purification of the material are presented and discussed. Completely separated uranium materials of known production date were distributed among the laboratories, and the samples were dated according to routine laboratory procedures by the measurement of the (230)Th/(234)U ratio. The measurement results were in good agreement with the known production date showing that the concept for preparing uranium age dating reference material based on complete separation is valid. Detailed knowledge of the laboratory procedures used for uranium age dating allows the identification of possible improvements in the current protocols and the development of improved practice in the future. The availability of age dating reference materials as well as the evolvement of the age dating best-practice protocol will increase the relevance and applicability of age dating as part of the tool-kit available for nuclear forensic investigations.

  20. Developing a reference material for diffusion-controlled formaldehyde emissions testing.

    PubMed

    Liu, Zhe; Liu, Xiaoyu; Zhao, Xiaomin; Cox, Steven S; Little, John C

    2013-11-19

    Formaldehyde, a known human carcinogen and mucous membrane irritant, is emitted from a variety of building materials and indoor furnishings. The drive to improve building energy efficiency by decreasing ventilation rates increases the need to better understand emissions from indoor products and to identify and develop lower emitting materials. To help meet this need, formaldehyde emissions from indoor materials are typically measured using environmental chambers. However, chamber testing results are frequently inconsistent and provide little insight into the mechanisms governing emissions. This research addresses these problems by (1) developing a reference formaldehyde emissions source that can be used to validate chamber testing methods for characterization of dynamic sources of formaldehyde emissions and (2) demonstrating that emissions from finite formaldehyde sources can be predicted using a fundamental mass-transfer model. Formaldehyde mass-transfer mechanisms are elucidated, providing practical approaches for developing diffusion-controlled reference materials that mimic actual sources. The fundamental understanding of emissions mechanisms can be used to improve emissions testing and guide future risk reduction actions.

  1. Developing a reference material for diffusion-controlled formaldehyde emissions testing.

    PubMed

    Liu, Zhe; Liu, Xiaoyu; Zhao, Xiaomin; Cox, Steven S; Little, John C

    2013-11-19

    Formaldehyde, a known human carcinogen and mucous membrane irritant, is emitted from a variety of building materials and indoor furnishings. The drive to improve building energy efficiency by decreasing ventilation rates increases the need to better understand emissions from indoor products and to identify and develop lower emitting materials. To help meet this need, formaldehyde emissions from indoor materials are typically measured using environmental chambers. However, chamber testing results are frequently inconsistent and provide little insight into the mechanisms governing emissions. This research addresses these problems by (1) developing a reference formaldehyde emissions source that can be used to validate chamber testing methods for characterization of dynamic sources of formaldehyde emissions and (2) demonstrating that emissions from finite formaldehyde sources can be predicted using a fundamental mass-transfer model. Formaldehyde mass-transfer mechanisms are elucidated, providing practical approaches for developing diffusion-controlled reference materials that mimic actual sources. The fundamental understanding of emissions mechanisms can be used to improve emissions testing and guide future risk reduction actions. PMID:24102115

  2. Determination of perfluorinated alkyl acid concentrations in biological standard reference materials.

    PubMed

    Reiner, Jessica L; O'Connell, Steven G; Butt, Craig M; Mabury, Scott A; Small, Jeff M; De Silva, Amila O; Muir, Derek C G; Delinsky, Amy D; Strynar, Mark J; Lindstrom, Andrew B; Reagen, William K; Malinsky, Michelle; Schäfer, Sandra; Kwadijk, Christiaan J A F; Schantz, Michele M; Keller, Jennifer M

    2012-11-01

    Standard reference materials (SRMs) are homogeneous, well-characterized materials used to validate measurements and improve the quality of analytical data. The National Institute of Standards and Technology (NIST) has a wide range of SRMs that have mass fraction values assigned for legacy pollutants. These SRMs can also serve as test materials for method development, method validation, and measurement for contaminants of emerging concern. Because inter-laboratory comparison studies have revealed substantial variability of measurements of perfluoroalkyl acids (PFAAs), future analytical measurements will benefit from determination of consensus values for PFAAs in SRMs to provide a means to demonstrate method-specific performance. To that end, NIST, in collaboration with other groups, has been measuring concentrations of PFAAs in a variety of SRMs. Here we report levels of PFAAs and perfluorooctane sulfonamide (PFOSA) determined in four biological SRMs: fish tissue (SRM 1946 Lake Superior Fish Tissue, SRM 1947 Lake Michigan Fish Tissue), bovine liver (SRM 1577c), and mussel tissue (SRM 2974a). We also report concentrations for three in-house quality-control materials: beluga whale liver, pygmy sperm whale liver, and white-sided dolphin liver. Measurements in SRMs show an array of PFAAs, with perfluorooctane sulfonate (PFOS) being the most frequently detected. Reference and information values are reported for PFAAs measured in these biological SRMs. PMID:22476786

  3. 230Th-234U Model-Ages of Some Uranium Standard Reference Materials

    SciTech Connect

    Williams, R W; Gaffney, A M; Kristo, M J; Hutcheon, I D

    2009-05-28

    The 'age' of a sample of uranium is an important aspect of a nuclear forensic investigation and of the attribution of the material to its source. To the extent that the sample obeys the standard rules of radiochronometry, then the production ages of even very recent material can be determined using the {sup 230}Th-{sup 234}U chronometer. These standard rules may be summarized as (a) the daughter/parent ratio at time=zero must be known, and (b) there has been no daughter/parent fractionation since production. For most samples of uranium, the 'ages' determined using this chronometer are semantically 'model-ages' because (a) some assumption of the initial {sup 230}Th content in the sample is required and (b) closed-system behavior is assumed. The uranium standard reference materials originally prepared and distributed by the former US National Bureau of Standards and now distributed by New Brunswick Laboratory as certified reference materials (NBS SRM = NBL CRM) are good candidates for samples where both rules are met. The U isotopic standards have known purification and production dates, and closed-system behavior in the solid form (U{sub 3}O{sub 8}) may be assumed with confidence. We present here {sup 230}Th-{sup 234}U model-ages for several of these standards, determined by isotope dilution mass spectrometry using a multicollector ICP-MS, and compare these ages with their known production history.

  4. Development of a certified reference material for genetically modified potato with altered starch composition.

    PubMed

    Broothaerts, Wim; Corbisier, Philippe; Emons, Hendrik; Emteborg, Håkan; Linsinger, Thomas P J; Trapmann, Stefanie

    2007-06-13

    The presence of genetically modified organisms (GMOs) in food and feed products is subject to regulation in the European Union (EU) and elsewhere. As part of the EU authorization procedure for GMOs intended for food and feed use, reference materials must be produced for the quality control of measurements to quantify the GMOs. Certified reference materials (CRMs) are available for a range of herbicide- and insect-resistant genetically modified crops such as corn, soybean, and cotton. Here the development of the first CRM for a GMO that differs from its non-GMO counterpart in a major compositional constituent, that is, starch, is described. It is shown that the modification of the starch composition of potato (Solanum tuberosum L.) tubers, together with other characteristics of the delivered materials, have important consequences for the certification strategy. Moreover, the processing and characterization of the EH92-527-1 potato material required both new and modified procedures, different from those used routinely for CRMs produced from genetically modified seeds.

  5. Hf Isotope Geochemistry of USGS Reference Materials and Various Labware: Insight into Potential Contaminant Sources

    NASA Astrophysics Data System (ADS)

    Weis, D.; Nobre Silva, I.; Kieffer, B.; Barling, J.; Pretorius, W.; Maerschalk, C.

    2005-12-01

    We have undertaken a high-precision geochemical and isotopic study of USGS reference materials by HR-ICP-MS, TIMS and MC-ICP-MS, including basalt (BCR-1,2; BHVO-1,2), andesite (AGV-1,2), rhyolite (RGM-1), syenite (STM-1,2), granodiorite (GSP-2), and granite (G-2,3). Only a few 176Hf/177Hf results are published on these materials and with the increased use of MC-ICP-MS it is critical to build a solid reference database. Standard hotplate dissolution was used, except for granitoid compositions where it involved a high-pressure bomb procedure. The reproducibility of 176Hf/177Hf is better than 100 ppm for granitoid compositions (G-2: 0.282523±8; G-3: 0.282505±20; GSP-2: 0.282059±27) and better than 65 ppm for basaltic/andesitic compositions in glassware and better than 30 ppm in teflon (BCR-2: 0.282872±9; BHVO-2: 0.283103±6). Overall, our results agree with the rare published data (BCR-1&2, BHVO-1 and RGM-1). Slight differences appear depending on the chemical procedure used to separate Hf and the type of labware used. There are systematic shifts in 176Hf/177Hf for basaltic compositions towards lower values (by 100-150 ppm) when non-teflon material is used. As a result, we then carried out a systematic trace element and isotopic study of various labware, including borosilicate glass and quartz columns and frits. Maximum concentrations (in ppm) of these materials (in the order listed above) are: Hf=16-0.3-22, Nd=0.8-0.1-23, Sr=8-0.08-16, Pb=1.4-0.5-14. The frit material appears the most variable in elemental concentration and isotopic composition, which might reflect various accumulations resulting from column chemistry. 176Hf/177Hf is 0.282198±4 in borosilicate glass and even lower in some of the frit material (<0.28195). Only a small amount of such unradiogenic material can account for the shifts observed in basaltic rocks. Our systematic study shows that careful analyses of rock reference materials with different compositional matrices are necessary, in

  6. Hf isotope compositions of U.S. Geological Survey reference materials

    NASA Astrophysics Data System (ADS)

    Weis, Dominique; Kieffer, Bruno; Hanano, Diane; Nobre Silva, Inês; Barling, Jane; Pretorius, Wilma; Maerschalk, Claude; Mattielli, Nadine

    2007-06-01

    A systematic multi-isotopic and trace element characterization of U.S. Geological Survey reference materials has been carried out at the Pacific Centre for Isotopic and Geochemical Research, University of British Columbia. Values of 176Hf/177Hf are recommended for the following reference materials (mean ±2 SD): G-2: 0.282523 ± 6; G-3: 0.282518 ± 1; GSP-2: 0.281949 ± 8; RGM-1: 0.283017 ± 13; STM-1: 0.283019 ± 12; STM-2: 0.283021 ± 5; BCR-1: 0.282875 ± 8; BCR-2: 0.282870 ± 8; BHVO-1: 0.283106 ± 12; BHVO-2: 0.283105 ± 11; AGV-1: 0.282979 ± 6; and AGV-2: 0.282984 ± 9. Reproducibility is better than 50 ppm for the granitoid compositions and better than 40 ppm for the basaltic/andesitic compositions. For the isotopic analyses acquired early in this project on glass columns, Hf isotopic analyses from several of the reference materials were significantly less reproducible than Nd and Sr isotopic analyses determined from the same sample dissolution. The 176Hf/177Hf ratios for relatively radiogenic compositions (BCR-1, 2; BHVO-1, 2; RGM-1) were shifted systematically toward lower values by 100-150 ppm when a borosilicate primary column was used. Although systematic, the shift for felsic compositions was generally within analytical error, except for GSP-2, which has a very low Hf isotopic ratio, where the shift was to higher 176Hf/177Hf. Trace element and isotopic characterization of the borosilicate glass column, borosilicate frits, and quartz columns reveals extremely variable levels of trace elements. The 176Hf/177Hf ratios for these materials are very unradiogenic (borosilicate glass <0.28220 frit = 0.28193 ± 4). The borosilicate frit material appears to be the most variable in elemental concentration and isotopic composition. The quartz material has very low levels (material (22 ppm) indicate that only small amounts of such unradiogenic

  7. Predicting the preservation of cultural artefacts and buried materials in soil.

    PubMed

    Kibblewhite, Mark; Tóth, Gergely; Hermann, Tamás

    2015-10-01

    This study identifies factors affecting the fate of buried objects in soil and develops a method for assessing where preservation of different materials and stratigraphic evidence is more or less likely in the landscape. The results inform the extent of the cultural service that soil supports by preserving artefacts from and information about past societies. They are also relevant to predicting the state of existing and planned buried infrastructure and the persistence of materials spread on land. Soils are variable and preserve different materials and stratigraphic evidence differently. This study identifies the material and soil properties that affect preservation and relates these to soil types; it assesses their preservation capacities for bones, teeth and shells, organic materials, metals (Au, Ag, Cu, Fe, Pb and bronze), ceramics, glass and stratigraphic evidence. Preservation of Au, Pb and ceramics, glass and phytoliths is good in most soils but degradation rates of other materials (e.g. Fe and organic materials) is strongly influenced by soil type. A method is proposed for using data on the distribution of soil types to map the variable preservation capacities of soil for different materials. This is applied at a continental scale across the EU for bones, teeth and shells, organic materials, metals (Cu, bronze and Fe) and stratigraphic evidence. The maps produced demonstrate how soil provides an extensive but variable preservation of buried objects.

  8. Reference Material Kydex(registered trademark)-100 Test Data Message for Flammability Testing

    NASA Technical Reports Server (NTRS)

    Engel, Carl D.; Richardson, Erin; Davis, Eddie

    2003-01-01

    The Marshall Space Flight Center (MSFC) Materials and Processes Technical Information System (MAPTIS) database contains, as an engineering resource, a large amount of material test data carefully obtained and recorded over a number of years. Flammability test data obtained using Test 1 of NASA-STD-6001 is a significant component of this database. NASA-STD-6001 recommends that Kydex 100 be used as a reference material for testing certification and for comparison between test facilities in the round-robin certification testing that occurs every 2 years. As a result of these regular activities, a large volume of test data is recorded within the MAPTIS database. The activity described in this technical report was undertaken to mine the database, recover flammability (Test 1) Kydex 100 data, and review the lessons learned from analysis of these data.

  9. On the status of IAEA delta-13C stable isotope reference materials.

    NASA Astrophysics Data System (ADS)

    Assonov, Sergey; Groening, Manfred; Fajgelj, Ales

    2016-04-01

    For practical reasons all isotope measurements are performed on relative scales realized through the use of international, scale-defining primary standards. In fact these standards were materials (artefacts, similar to prototypes of meter and kg) selected based on their properties. The VPDB delta-13C scale is realised via two highest-level reference materials NBS19 and LSVEC, the first defining the scale and the second aimed to normalise lab-to-lab calibrations. These two reference materials (RMs) have been maintained and distributed by IAEA and NIST. The priority task is to maintain these primary RMs at the required uncertainty level, thus ensuring the long-term scale consistency. The second task is to introduce replacements when needed (currently for exhausted NBS19, work in progress). The next is to produce a family of lower level RMs (secondary, tertiary) addressing needs of various applications (with different delta values, in different physical-chemical forms) and their needs for the uncertainty; these RMs should be traceable to the highest level RMs. Presently three is a need for a range of RMs addressing existing and newly emerging analytical techniques (e.g. optical isotopic analysers) in form of calibrated CO2 gases with different delta-13C values. All that implies creating a family of delta-13C stable isotope reference materials. Presently IAEA works on replacement for NBS19 and planning new RMs. Besides, we found that LSVEC (introduced as second anchor for the VPDB scale in 2006) demonstrate a considerable scatter of its delta-13C value which implies a potential bias of the property value and increased value uncertainty which may conflict with uncertainty requirements for atmospheric monitoring. That is not compatible with the status of LSVEC, and therefore it should be replaced as soon as possible. The presentation will give an overview of the current status, the strategic plan of developments and the near future steps.

  10. Development of botanical and fish oil standard reference materials for fatty acids.

    PubMed

    Schantz, Michele M; Sander, Lane C; Sharpless, Katherine E; Wise, Stephen A; Yen, James H; NguyenPho, Agnes; Betz, Joseph M

    2013-05-01

    As part of a collaboration with the National Institutes of Health's Office of Dietary Supplements and the Food and Drug Administration's Center for Drug Evaluation and Research, the National Institute of Standards and Technology has developed Standard Reference Material (SRM) 3274 Botanical Oils Containing Omega-3 and Omega-6 Fatty Acids and SRM 3275 Omega-3 and Omega-6 Fatty Acids in Fish Oil. SRM 3274 consists of one ampoule of each of four seed oils (3274-1 Borage (Borago officinalis), 3274-2 Evening Primrose (Oenothera biennis), 3274-3 Flax (Linium usitatissimum), and 3274-4 Perilla (Perilla frutescens)), and SRM 3275 consists of two ampoules of each of three fish oils (3275-1 a concentrate high in docosahexaenoic acid, 3275-2 an anchovy oil high in docosahexaenoic acid and eicosapentaenoic acid, and 3275-3 a concentrate containing 60% long-chain omega-3 fatty acids). Each oil has certified and reference mass fraction values for up to 20 fatty acids. The fatty acid mass fraction values are based on results from analyses using gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS). These SRMs will complement other reference materials currently available with mass fractions for similar analytes and are part of a series of SRMs being developed for dietary supplements. PMID:23371533

  11. Development of botanical and fish oil standard reference materials for fatty acids.

    PubMed

    Schantz, Michele M; Sander, Lane C; Sharpless, Katherine E; Wise, Stephen A; Yen, James H; NguyenPho, Agnes; Betz, Joseph M

    2013-05-01

    As part of a collaboration with the National Institutes of Health's Office of Dietary Supplements and the Food and Drug Administration's Center for Drug Evaluation and Research, the National Institute of Standards and Technology has developed Standard Reference Material (SRM) 3274 Botanical Oils Containing Omega-3 and Omega-6 Fatty Acids and SRM 3275 Omega-3 and Omega-6 Fatty Acids in Fish Oil. SRM 3274 consists of one ampoule of each of four seed oils (3274-1 Borage (Borago officinalis), 3274-2 Evening Primrose (Oenothera biennis), 3274-3 Flax (Linium usitatissimum), and 3274-4 Perilla (Perilla frutescens)), and SRM 3275 consists of two ampoules of each of three fish oils (3275-1 a concentrate high in docosahexaenoic acid, 3275-2 an anchovy oil high in docosahexaenoic acid and eicosapentaenoic acid, and 3275-3 a concentrate containing 60% long-chain omega-3 fatty acids). Each oil has certified and reference mass fraction values for up to 20 fatty acids. The fatty acid mass fraction values are based on results from analyses using gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS). These SRMs will complement other reference materials currently available with mass fractions for similar analytes and are part of a series of SRMs being developed for dietary supplements.

  12. Isotopic composition ( 238U/ 235U) of some commonly used uranium reference materials

    NASA Astrophysics Data System (ADS)

    Condon, Daniel J.; McLean, Noah; Noble, Stephen R.; Bowring, Samuel A.

    2010-12-01

    We have determined 238U/ 235U ratios for a suite of commonly used natural (CRM 112a, SRM 950a, and HU-1) and synthetic (IRMM 184 and CRM U500) uranium reference materials by thermal ionisation mass-spectrometry (TIMS) using the IRMM 3636 233U- 236U double spike to accurately correct for mass fractionation. Total uncertainty on the 238U/ 235U determinations is estimated to be <0.02% (2σ). These natural 238U/ 235U values are different from the widely used 'consensus' value (137.88), with each standard having lower 238U/ 235U values by up to 0.08%. The 238U/ 235U ratio determined for CRM U500 and IRMM 184 are within error of their certified values; however, the total uncertainty for CRM U500 is substantially reduced (from 0.1% to 0.02%). These reference materials are commonly used to assess mass-spectrometer performance and accuracy, calibrate isotope tracers employed in U, U-Th and U-Pb isotopic studies, and as a reference for terrestrial and meteoritic 238U/ 235U variations. These new 238U/ 235U values will thus provide greater accuracy and reduced uncertainty for a wide variety of isotopic determinations.

  13. Statistical Analysis of a Round-Robin Measurement Survey of Two Candidate Materials for a Seebeck Coefficient Standard Reference Material

    PubMed Central

    Lu, Z. Q. J.; Lowhorn, N. D.; Wong-Ng, W.; Zhang, W.; Thomas, E. L.; Otani, M.; Green, M. L.; Tran, T. N.; Caylor, C.; Dilley, N. R.; Downey, A.; Edwards, B.; Elsner, N.; Ghamaty, S.; Hogan, T.; Jie, Q.; Li, Q.; Martin, J.; Nolas, G.; Obara, H.; Sharp, J.; Venkatasubramanian, R.; Willigan, R.; Yang, J.; Tritt, T.

    2009-01-01

    In an effort to develop a Standard Reference Material (SRM™) for Seebeck coefficient, we have conducted a round-robin measurement survey of two candidate materials—undoped Bi2Te3 and Constantan (55 % Cu and 45 % Ni alloy). Measurements were performed in two rounds by twelve laboratories involved in active thermoelectric research using a number of different commercial and custom-built measurement systems and techniques. In this paper we report the detailed statistical analyses on the interlaboratory measurement results and the statistical methodology for analysis of irregularly sampled measurement curves in the interlaboratory study setting. Based on these results, we have selected Bi2Te3 as the prototype standard material. Once available, this SRM will be useful for future interlaboratory data comparison and instrument calibrations. PMID:27504212

  14. History of reference materials for food and nutrition metrology: As represented in the series of BERM Symposia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Establishment of a metrology-based measurement system requires the solid foundation of traceability of measurements to available, appropriate certified reference materials (CRM). In the early 1970s the first “biological” Reference Material (RM) of Bowens Kale, Orchard Leaves, and Bovine Liver from ...

  15. Sensitivity of ecological soil-screening levels for metals to exposure model parameterization and toxicity reference values.

    PubMed

    Sample, Bradley E; Fairbrother, Anne; Kaiser, Ashley; Law, Sheryl; Adams, Bill

    2014-10-01

    Ecological soil-screening levels (Eco-SSLs) were developed by the United States Environmental Protection Agency (USEPA) for the purposes of setting conservative soil screening values that can be used to eliminate the need for further ecological assessment for specific analytes at a given site. Ecological soil-screening levels for wildlife represent a simplified dietary exposure model solved in terms of soil concentrations to produce exposure equal to a no-observed-adverse-effect toxicity reference value (TRV). Sensitivity analyses were performed for 6 avian and mammalian model species, and 16 metals/metalloids for which Eco-SSLs have been developed. The relative influence of model parameters was expressed as the absolute value of the range of variation observed in the resulting soil concentration when exposure is equal to the TRV. Rank analysis of variance was used to identify parameters with greatest influence on model output. For both birds and mammals, soil ingestion displayed the broadest overall range (variability), although TRVs consistently had the greatest influence on calculated soil concentrations; bioavailability in food was consistently the least influential parameter, although an important site-specific variable. Relative importance of parameters differed by trophic group. Soil ingestion ranked 2nd for carnivores and herbivores, but was 4th for invertivores. Different patterns were exhibited, depending on which parameter, trophic group, and analyte combination was considered. The approach for TRV selection was also examined in detail, with Cu as the representative analyte. The underlying assumption that generic body-weight-normalized TRVs can be used to derive protective levels for any species is not supported by the data. Whereas the use of site-, species-, and analyte-specific exposure parameters is recommended to reduce variation in exposure estimates (soil protection level), improvement of TRVs is more problematic.

  16. Sensitivity of ecological soil-screening levels for metals to exposure model parameterization and toxicity reference values

    PubMed Central

    Sample, Bradley E; Fairbrother, Anne; Kaiser, Ashley; Law, Sheryl; Adams, Bill

    2014-01-01

    Ecological soil-screening levels (Eco-SSLs) were developed by the United States Environmental Protection Agency (USEPA) for the purposes of setting conservative soil screening values that can be used to eliminate the need for further ecological assessment for specific analytes at a given site. Ecological soil-screening levels for wildlife represent a simplified dietary exposure model solved in terms of soil concentrations to produce exposure equal to a no-observed-adverse-effect toxicity reference value (TRV). Sensitivity analyses were performed for 6 avian and mammalian model species, and 16 metals/metalloids for which Eco-SSLs have been developed. The relative influence of model parameters was expressed as the absolute value of the range of variation observed in the resulting soil concentration when exposure is equal to the TRV. Rank analysis of variance was used to identify parameters with greatest influence on model output. For both birds and mammals, soil ingestion displayed the broadest overall range (variability), although TRVs consistently had the greatest influence on calculated soil concentrations; bioavailability in food was consistently the least influential parameter, although an important site-specific variable. Relative importance of parameters differed by trophic group. Soil ingestion ranked 2nd for carnivores and herbivores, but was 4th for invertivores. Different patterns were exhibited, depending on which parameter, trophic group, and analyte combination was considered. The approach for TRV selection was also examined in detail, with Cu as the representative analyte. The underlying assumption that generic body-weight–normalized TRVs can be used to derive protective levels for any species is not supported by the data. Whereas the use of site-, species-, and analyte-specific exposure parameters is recommended to reduce variation in exposure estimates (soil protection level), improvement of TRVs is more problematic. Environ Toxicol Chem 2014

  17. Laboratory evaluation of frozen soil target materials with a fused interface.

    SciTech Connect

    Bronowski, David R.; Lee, Moo Yul

    2004-10-01

    To investigate the performance of artificial frozen soil materials with a fused interface, split tension (or 'Brazilian') tests and unconfined uniaxial compression tests were carried out in a low temperature environmental chamber. Intact and fused specimens were fabricated from four different soil mixtures (962: clay-rich soil with bentonite; DNA1: clay-poor soil; DNA2: clay-poor soil with vermiculite; and DNA3: clay-poor soil with perlite). Based on the 'Brazilian' test results and density measurements, the DNA3 mixture was selected to closely represent the mechanical properties of the Alaskan frozen soil. The healed-interface by the same soil layer sandwiched between two blocks of the same material yielded the highest 'Brazilian' tensile strength of the interface. Based on unconfined uniaxial compression tests, the frictional strength of the fused DNA3 specimens with the same soil appears to exceed the shear strength of the intact specimen.

  18. Reference waste forms and packing material for the Nevada Nuclear Waste Storage Investigations Project

    SciTech Connect

    Oversby, V.M.

    1984-03-30

    The Lawrence Livermore National Laboratory (LLNL), Livermore, Calif., has been given the task of designing and verifying the performance of waste packages for the Nevada Nuclear Waste Storage Investigations (NNWSI) Project. NNWSI is studying the suitability of the tuffaceous rocks at Yucca Mountain, Nevada Test Site, for the potential construction of a high-level nuclear waste repository. This report gives a summary description of the three waste forms for which LLNL is designing waste packages: spent fuel, either as intact assemblies or as consolidated fuel pins, reprocessed commercial high-level waste in the form of borosilicate glass, and reprocessed defense high-level waste from the Defense Waste Processing Facility in Aiken, S.C. Reference packing material for use with the alternative waste package design for spent fuel is also described. 14 references, 8 figures, 20 tables.

  19. Results of a Saxitoxin Proficiency Test Including Characterization of Reference Material and Stability Studies

    PubMed Central

    Harju, Kirsi; Rapinoja, Marja-Leena; Avondet, Marc-André; Arnold, Werner; Schär, Martin; Luginbühl, Werner; Kremp, Anke; Suikkanen, Sanna; Kankaanpää, Harri; Burrell, Stephen; Söderström, Martin; Vanninen, Paula

    2015-01-01

    A saxitoxin (STX) proficiency test (PT) was organized as part of the Establishment of Quality Assurance for the Detection of Biological Toxins of Potential Bioterrorism Risk (EQuATox) project. The aim of this PT was to provide an evaluation of existing methods and the European laboratories’ capabilities for the analysis of STX and some of its analogues in real samples. Homogenized mussel material and algal cell materials containing paralytic shellfish poisoning (PSP) toxins were produced as reference sample matrices. The reference material was characterized using various analytical methods. Acidified algal extract samples at two concentration levels were prepared from a bulk culture of PSP toxins producing dinoflagellate Alexandrium ostenfeldii. The homogeneity and stability of the prepared PT samples were studied and found to be fit-for-purpose. Thereafter, eight STX PT samples were sent to ten participating laboratories from eight countries. The PT offered the participating laboratories the possibility to assess their performance regarding the qualitative and quantitative detection of PSP toxins. Various techniques such as official Association of Official Analytical Chemists (AOAC) methods, immunoassays, and liquid chromatography-mass spectrometry were used for sample analyses. PMID:26602927

  20. Development and certification of a reference material for Fusarium mycotoxins in wheat flour.

    PubMed

    Köppen, Robert; Bremser, Wolfram; Rasenko, Tatjana; Koch, Matthias

    2013-05-01

    Deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEN) are toxic secondary metabolites produced by several species of Fusarium fungi. These mycotoxins are often found together in a large variety of cereal-based foods, which are regulated by maximum content levels of DON and ZEN. To date, suitable certified reference materials (CRM) intended for quality control purposes are lacking for these Fusarium mycotoxins. In order to overcome this lack, the first CRM for the determination of DON, NIV and ZEN in naturally contaminated wheat flour (ERM®-BC600) was developed in the framework of a European Reference Materials (ERM®) project. This article describes and discusses the whole process of ERM®-BC600 development, including material preparation, homogeneity and stability studies, and an interlaboratory comparison study for certification. A total of 21 selected expert laboratories from different European countries with documented expertise in the field of mycotoxin analysis took part in the certification study using various gas and liquid chromatographic methods. The certified values and their corresponding expanded uncertainties (k = 2) were assigned in full compliance with the requirements of ISO Guide 35 and are as follows: 102 ± 11 μg kg(-1) for DON, 1000 ± 130 μg kg(-1) for NIV and 90 ± 8 μg kg(-1) for ZEN.

  1. Results of a Saxitoxin Proficiency Test Including Characterization of Reference Material and Stability Studies.

    PubMed

    Harju, Kirsi; Rapinoja, Marja-Leena; Avondet, Marc-André; Arnold, Werner; Schär, Martin; Luginbühl, Werner; Kremp, Anke; Suikkanen, Sanna; Kankaanpää, Harri; Burrell, Stephen; Söderström, Martin; Vanninen, Paula

    2015-11-25

    A saxitoxin (STX) proficiency test (PT) was organized as part of the Establishment of Quality Assurance for the Detection of Biological Toxins of Potential Bioterrorism Risk (EQuATox) project. The aim of this PT was to provide an evaluation of existing methods and the European laboratories' capabilities for the analysis of STX and some of its analogues in real samples. Homogenized mussel material and algal cell materials containing paralytic shellfish poisoning (PSP) toxins were produced as reference sample matrices. The reference material was characterized using various analytical methods. Acidified algal extract samples at two concentration levels were prepared from a bulk culture of PSP toxins producing dinoflagellate Alexandrium ostenfeldii. The homogeneity and stability of the prepared PT samples were studied and found to be fit-for-purpose. Thereafter, eight STX PT samples were sent to ten participating laboratories from eight countries. The PT offered the participating laboratories the possibility to assess their performance regarding the qualitative and quantitative detection of PSP toxins. Various techniques such as official Association of Official Analytical Chemists (AOAC) methods, immunoassays, and liquid chromatography-mass spectrometry were used for sample analyses.

  2. Development of apple certified reference material for quantification of organophosphorus and pyrethroid pesticides.

    PubMed

    Otake, Takamitsu; Yarita, Takashi; Aoyagi, Yoshie; Kuroda, Youko; Numata, Masahiko; Iwata, Hitoshi; Watai, Masatoshi; Mitsuda, Hitoshi; Fujikawa, Takashi; Ota, Hidekazu

    2013-06-01

    An apple certified reference material for the analysis of pesticide residues was issued by the National Metrology Institute of Japan. Organophosphorus and pyrethroid pesticides were sprayed on apples, and these were used as raw materials of certified reference material. The harvested apples were cut into small pieces, freeze-dried, pulverized, sieved, placed into 200 brown glass bottles (3g each), and sterilized by γ-irradiation. Stability and homogeneity assessment was performed, and the relative uncertainties due to instability (for an expiry date of 32 months) and inhomogeneity were 10.3-25.0% and 4.0-6.8%, respectively. The characterization was carried out using multiple analytical methods to ensure the reliability of analytical results; the values of target pesticides were obtained by isotope dilution mass spectrometry. Certified values were 2.28 ± 0.82 mg/kg for diazinon, 3.14 ± 0.79 mg/kg for fenitrothion, 1.55 ± 0.81 mg/kg for cypermethrin, and 2.81 ± 0.70 mg/kg for permethrin.

  3. Evaluation of a fungal collection as certified reference material producer and as a biological resource center.

    PubMed

    Forti, Tatiana; Souto, Aline da S S; do Nascimento, Carlos Roberto S; Nishikawa, Marilia M; Hubner, Marise T W; Sabagh, Fernanda P; Temporal, Rosane Maria; Rodrigues, Janaína M; da Silva, Manuela

    2016-01-01

    Considering the absence of standards for culture collections and more specifically for biological resource centers in the world, in addition to the absence of certified biological material in Brazil, this study aimed to evaluate a Fungal Collection from Fiocruz, as a producer of certified reference material and as Biological Resource Center (BRC). For this evaluation, a checklist based on the requirements of ABNT ISO GUIA34:2012 correlated with the ABNT NBR ISO/IEC17025:2005, was designed and applied. Complementing the implementation of the checklist, an internal audit was performed. An evaluation of this Collection as a BRC was also conducted following the requirements of the NIT-DICLA-061, the Brazilian internal standard from Inmetro, based on ABNT NBR ISO/IEC 17025:2005, ABNT ISO GUIA 34:2012 and OECD Best Practice Guidelines for BRCs. This was the first time that the NIT DICLA-061 was applied in a culture collection during an internal audit. The assessments enabled the proposal for the adequacy of this Collection to assure the implementation of the management system for their future accreditation by Inmetro as a certified reference material producer as well as its future accreditation as a Biological Resource Center according to the NIT-DICLA-061. PMID:26991280

  4. The determination of water in crude oil and transformer oil reference materials.

    PubMed

    Margolis, Sam A; Hagwood, Charles

    2003-05-01

    The measurement of the amount of water in oils is of significant economic importance to the industrial community, particularly to the electric power and crude oil industries. The amount of water in transformer oils is critical to their normal function and the amount of water in crude oils affects the cost of the crude oil at the well head, the pipeline, and the refinery. Water in oil Certified Reference Materials (CRM) are essential for the accurate calibration of instruments that are used by these industries. Three NIST Standard Reference Materials (SRMs) have been prepared for this purpose. The water in these oils has been measured by both coulometric and volumetric Karl Fischer methods. The compounds (such as sulfur compounds) that interfere with the Karl Fischer reaction (interfering substances) and inflate the values for water by also reacting with iodine have been measured coulometrically. The measured water content of Reference Material (RM) 8506a Transformer Oil is 12.1+/-1.9 mg kg(-1) (plus an additional 6.2+/-0.9 mg kg(-1) of interfering substances). The measured water content of SRM 2722 Sweet Crude Oil, is 99+/-6 mg kg(-1) (plus an additional 5+/-2 mg kg(-1) of interfering substances). The measured water content of SRM 2721 Sour Crude Oil, is 134+/-18 mg kg(-1) plus an additional 807+/-43 mg kg(-1) of interfering substances. Interlaboratory studies conducted with these oil samples (using SRM 2890, water saturated 1-octanol, as a calibrant) are reported. Some of the possible sources of bias in these measurements were identified, These include: improperly calibrated instruments, inability to measure the calibrant accurately, Karl Fischer reagent selection, and volatilization of the interfering substances in SRM 2721.

  5. Preparation and certification of Re-Os dating reference materials: Molybdenites HLP and JDC

    USGS Publications Warehouse

    Du, A.; Wu, S.; Sun, D.; Wang, Shaoming; Qu, W.; Markey, R.; Stain, H.; Morgan, J.; Malinovskiy, D.

    2004-01-01

    Two Re-Os dating reference material molybdenites were prepared. Molybdenite JDC and molybdenite HLP are from a carbonate vein-type molybdenum-(lead)- uranium deposit in the Jinduicheng-Huanglongpu area of Shaanxi province, China. The samples proved to be homogeneous, based on the coefficient of variation of analytical results and an analysis of variance test. The sampling weight was 0.1 g for JDC and 0.025 g for HLP. An isotope dilution method was used for the determination of Re and Os. Sample decomposition and preconcentration of Re and Os prior to measurement were accomplished using a variety of methods: acid digestion, alkali fusion, ion exchange and solvent extraction. Negative thermal ionisation mass spectrometry and inductively coupled plasma-mass spectrometry were used for the determination of Re and 187Os concentration and isotope ratios. The certified values include the contents of Re and Os and the model ages. For HLP, the Re content was 283.8 ?? 6.2 ??g g-1, 187Os was 659 ?? 14 ng g-1 and the Re-Os model age was 221.4 ?? 5.6 Ma. For JDC, the Re content was 17.39 ?? 0.32 ng g-1, 187Os was 25.46 ?? 0.60 ng g-1 and the Re-Os model age was 139.6 ?? 3.8 Ma. Uncertainties for both certified reference materials are stated at the 95% level of confidence. Three laboratories (from three countries: P.R. China, USA, Sweden) joined in the certification programme. These certified reference materials are primarily useful for Re-Os dating of molybdenite, sulfides, black shale, etc.

  6. Effect of platform, reference material, and quantification model on enumeration of Enterococcus by quantitative PCR methods.

    PubMed

    Cao, Yiping; Sivaganesan, Mano; Kinzelman, Julie; Blackwood, A Denene; Noble, Rachel T; Haugland, Richard A; Griffith, John F; Weisberg, Stephen B

    2013-01-01

    Quantitative polymerase chain reaction (qPCR) is increasingly being used for the quantitative detection of fecal indicator bacteria in beach water. QPCR allows for same-day health warnings, and its application is being considered as an option for recreational water quality testing in the United States (USEPA, 2011. EPA-OW-2011-0466, FRL-9609-3, Notice of Availability of Draft Recreational Water Quality Criteria and Request for Scientific Views). However, transition of qPCR from a research tool to routine water quality testing requires information on how various method variations affect target enumeration. Here we compared qPCR performance and enumeration of enterococci in spiked and environmental water samples using three qPCR platforms (Applied Biosystem StepOnePlus™, the BioRad iQ™5 and the Cepheid SmartCycler(®) II), two reference materials (lyophilized cells and frozen cells on filters) and two comparative CT quantification models (ΔCT and ΔΔCT). Reference materials exerted the biggest influence, consistently affecting results by approximately 0.5 log(10) unit. Platform had the smallest effect, generally exerting <0.1 log(10) unit difference in final results. Quantification model led to small differences (0.04-0.2 log(10) unit) in this study with relatively uninhibited samples, but has the potential to cause as much as 8-fold (0.9 log(10) unit) difference in potentially inhibitory samples. Our findings indicate the need for a certified and centralized source of reference materials and additional studies to assess applicability of the quantification models in analyses of PCR inhibitory samples.

  7. Nature and Properties of Lateritic Soils Derived from Different Parent Materials in Taiwan

    PubMed Central

    2014-01-01

    The objective of this study was to investigate the physical, chemical, and mineralogical composition of lateritic soils in order to use these soils as potential commercial products for industrial application in the future. Five lateritic soils derived from various parent materials in Taiwan, including andesite, diluvium, shale stone, basalt, and Pleistocene deposit, were collected from the Bt1 level of soil samples. Based on the analyses, the Tungwei soil is an alfisol, whereas other lateritic soils are ultisol. Higher pH value of Tungwei is attributed to the large amounts of Ca2+ and Mg2+. Loupi and Pingchen soils would be the older lateritic soils because of the lower active iron ratio. For the iron minerals, the magnetic iron oxides such as major amounts of magnetite and maghemite were found for Tamshui and Tungwei lateritic soils, respectively. Lepidocrocite was only found in Soka soil and intermediate amounts of goethite were detected for Loupi and Pingchen soils. After Mg-saturated and K-saturated processes, major amounts of mixed layer were observed in Loupi and Soka soils, whereas the montmorillonite was only detected in Tungwei soil. The investigation results revealed that the parent materials would play an important role during soil weathering process and physical, chemical, and mineralogy compositions strongly affect the formation of lateritic soils. PMID:24883366

  8. Nature and properties of lateritic soils derived from different parent materials in Taiwan.

    PubMed

    Ko, Tzu-Hsing

    2014-01-01

    The objective of this study was to investigate the physical, chemical, and mineralogical composition of lateritic soils in order to use these soils as potential commercial products for industrial application in the future. Five lateritic soils derived from various parent materials in Taiwan, including andesite, diluvium, shale stone, basalt, and Pleistocene deposit, were collected from the Bt1 level of soil samples. Based on the analyses, the Tungwei soil is an alfisol, whereas other lateritic soils are ultisol. Higher pH value of Tungwei is attributed to the large amounts of Ca(2+) and Mg(2+). Loupi and Pingchen soils would be the older lateritic soils because of the lower active iron ratio. For the iron minerals, the magnetic iron oxides such as major amounts of magnetite and maghemite were found for Tamshui and Tungwei lateritic soils, respectively. Lepidocrocite was only found in Soka soil and intermediate amounts of goethite were detected for Loupi and Pingchen soils. After Mg-saturated and K-saturated processes, major amounts of mixed layer were observed in Loupi and Soka soils, whereas the montmorillonite was only detected in Tungwei soil. The investigation results revealed that the parent materials would play an important role during soil weathering process and physical, chemical, and mineralogy compositions strongly affect the formation of lateritic soils.

  9. Nature and properties of lateritic soils derived from different parent materials in Taiwan.

    PubMed

    Ko, Tzu-Hsing

    2014-01-01

    The objective of this study was to investigate the physical, chemical, and mineralogical composition of lateritic soils in order to use these soils as potential commercial products for industrial application in the future. Five lateritic soils derived from various parent materials in Taiwan, including andesite, diluvium, shale stone, basalt, and Pleistocene deposit, were collected from the Bt1 level of soil samples. Based on the analyses, the Tungwei soil is an alfisol, whereas other lateritic soils are ultisol. Higher pH value of Tungwei is attributed to the large amounts of Ca(2+) and Mg(2+). Loupi and Pingchen soils would be the older lateritic soils because of the lower active iron ratio. For the iron minerals, the magnetic iron oxides such as major amounts of magnetite and maghemite were found for Tamshui and Tungwei lateritic soils, respectively. Lepidocrocite was only found in Soka soil and intermediate amounts of goethite were detected for Loupi and Pingchen soils. After Mg-saturated and K-saturated processes, major amounts of mixed layer were observed in Loupi and Soka soils, whereas the montmorillonite was only detected in Tungwei soil. The investigation results revealed that the parent materials would play an important role during soil weathering process and physical, chemical, and mineralogy compositions strongly affect the formation of lateritic soils. PMID:24883366

  10. Evaluation of the sulfur isotopic composition and homogeneity of the Soufre de Lacq reference material

    USGS Publications Warehouse

    Carmody, R.W.; Seal, R.R., II

    1999-01-01

    Sulfur isotopic analysis of the elemental sulfur reference material Soufre de Lacq, prepared as silver sulfide by chromous chloride reduction and as copper sulfide by sealed-tube synthesis, indicates that Soufre de Lacq is isotopically homogeneous across different size fractions to within analytical uncertainty (??0.15???). The sulfur isotopic composition of aliquots of Soufre de Lacq prepared by these two techniques are identical to within analytical uncertainty. The mean sulfur isotopic composition for Soufre de Lacq prepared as silver sulfide and copper sulfide (relative to VCDT) is +16.20 ?? 0.15??? (1??).

  11. Standard wool fabric as a reference material. [for fire toxicity tests

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Cumming, H. J.

    1977-01-01

    Standard wool fabric is investigated as a potential reference material. A screening test method for relative toxicity exposes four albino male rats enclosed in a 4.2 liter hemispherical chamber to pyrolysis effluents produced by pyrolyzing a 1.00 g sample under a variety of test conditions (200-800 C with a 40 C/min heating rate). It is found that for fabrics containing 86-100% wool, animal response remains virtually unchanged, although a 100% wool fabric is preferred as it eliminates local composition differences as a source of variation.

  12. As(V) and P Competitive Sorption on Soils, By-Products and Waste Materials

    PubMed Central

    Rivas-Pérez, Ivana María; Paradelo-Núñez, Remigio; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María José; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-01-01

    Batch-type experiments were used to study competitive As(V) and P sorption on various soils and sorbent materials. The materials assayed were a forest soil, a vineyard soil, pyritic material, granitic material, coarsely and finely ground mussel shell, calcinated mussel shell ash, pine sawdust and slate processing fines. Competition between As(V) and P was pronounced in the case of both soils, granitic material, slate fines, both shells and pine sawdust, showing more affinity for P. Contrary, the pyritic material and mussel shell ash showed high and similar affinity for As(V) and P. These results could be useful to make a correct use of the soils and materials assayed when focusing on As and P removal in solid or liquid media, in circumstances where both pollutants may compete for sorption sites. PMID:26690456

  13. As(V) and P Competitive Sorption on Soils, By-Products and Waste Materials.

    PubMed

    Rivas-Pérez, Ivana María; Paradelo-Núñez, Remigio; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María José; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-12-01

    Batch-type experiments were used to study competitive As(V) and P sorption on various soils and sorbent materials. The materials assayed were a forest soil, a vineyard soil, pyritic material, granitic material, coarsely and finely ground mussel shell, calcinated mussel shell ash, pine sawdust and slate processing fines. Competition between As(V) and P was pronounced in the case of both soils, granitic material, slate fines, both shells and pine sawdust, showing more affinity for P. Contrary, the pyritic material and mussel shell ash showed high and similar affinity for As(V) and P. These results could be useful to make a correct use of the soils and materials assayed when focusing on As and P removal in solid or liquid media, in circumstances where both pollutants may compete for sorption sites.

  14. As(V) and P Competitive Sorption on Soils, By-Products and Waste Materials.

    PubMed

    Rivas-Pérez, Ivana María; Paradelo-Núñez, Remigio; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María José; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2015-12-01

    Batch-type experiments were used to study competitive As(V) and P sorption on various soils and sorbent materials. The materials assayed were a forest soil, a vineyard soil, pyritic material, granitic material, coarsely and finely ground mussel shell, calcinated mussel shell ash, pine sawdust and slate processing fines. Competition between As(V) and P was pronounced in the case of both soils, granitic material, slate fines, both shells and pine sawdust, showing more affinity for P. Contrary, the pyritic material and mussel shell ash showed high and similar affinity for As(V) and P. These results could be useful to make a correct use of the soils and materials assayed when focusing on As and P removal in solid or liquid media, in circumstances where both pollutants may compete for sorption sites. PMID:26690456

  15. Certification of the European Reference Soil Set (IRMM-443--EUROSOILS). Part II. Soil-pH in suspensions of water and CaCl2.

    PubMed

    Gawlik, B M; Lamberty, A; Pauwels, J; Blum, W E H; Mentler, A; Bussian, B; Eklo, O; Fox, K; Kördel, W; Hennecke, D; Maurer, T; Perrin-Ganier, C; Romero-Taboada, E; Szabo, G; Muntau, H

    2003-08-01

    IRMM-443 re-groups a set of six European Reference Soils (EUROSOILS), which had been certified for their adsorption coefficients for atrazine, 2,4-D and lindane (Certification of the European Reference Soil Set (IRMM-443-EUROSOILS)-Part I. Adsorption coefficients for atrazine, 2,4-D and lindane. Sci Total Environ, in press). The certification of these parameters was complemented by an additional certification of pH in suspension as well by the determination of indicative values for total nitrogen, organic and total carbon content. While Part I explained the principles of the value assignment process and discussed their application to the adsorption coefficients, Part II presents the certified values for pH as well as the indicative values for N(tot), C(tot) and C(org). In addition, the assessment of uncertainty components for stability and homogeneity, which have been included in the final uncertainty budget, is discussed.

  16. Certified Reference Material IAEA-446 for radionuclides in Baltic Sea seaweed.

    PubMed

    Pham, M K; Benmansour, M; Carvalho, F P; Chamizo, E; Degering, D; Engeler, C; Gascó, C; Gwynn, J P; Harms, A V; Hrnecek, E; Ibanez, F L; Ilchmann, C; Ikaheimonen, T; Kanisch, G; Kloster, M; Llaurado, M; Mauring, A; Møller, B; Morimoto, T; Nielsen, S P; Nies, H; Norrlid, L D R; Pettersson, H B L; Povinec, P P; Rieth, U; Samuelsson, C; Schikowski, J; Silobritiene, B V; Smedley, P A; Suplinska, M; Vartti, V-P; Vasileva, E; Wong, J; Zalewska, T; Zhou, W

    2014-05-01

    A Certified Reference Material (CRM) for radionuclides in seaweed (Fucus vesiculosus) from the Baltic Sea (IAEA-446) is described and the results of the certification process are presented. The (40)K, (137)Cs, (234)U and (239+240)Pu radionuclides were certified for this material, and information values for 12 other radionuclides ((90)Sr, (99)Tc, (210)Pb ((210)Po), (226)Ra, (228)Ra, (228)Th, (230)Th, (232)Th, (235)U, (238)U, (239)Pu and (240)Pu) are presented. The CRM can be used for Quality Assurance/Quality Control of analysis of radionuclides in seaweed and other biota samples, as well as for development and validation of analytical methods, and for training purposes.

  17. Certified Reference Material IAEA-446 for radionuclides in Baltic Sea seaweed.

    PubMed

    Pham, M K; Benmansour, M; Carvalho, F P; Chamizo, E; Degering, D; Engeler, C; Gascó, C; Gwynn, J P; Harms, A V; Hrnecek, E; Ibanez, F L; Ilchmann, C; Ikaheimonen, T; Kanisch, G; Kloster, M; Llaurado, M; Mauring, A; Møller, B; Morimoto, T; Nielsen, S P; Nies, H; Norrlid, L D R; Pettersson, H B L; Povinec, P P; Rieth, U; Samuelsson, C; Schikowski, J; Silobritiene, B V; Smedley, P A; Suplinska, M; Vartti, V-P; Vasileva, E; Wong, J; Zalewska, T; Zhou, W

    2014-05-01

    A Certified Reference Material (CRM) for radionuclides in seaweed (Fucus vesiculosus) from the Baltic Sea (IAEA-446) is described and the results of the certification process are presented. The (40)K, (137)Cs, (234)U and (239+240)Pu radionuclides were certified for this material, and information values for 12 other radionuclides ((90)Sr, (99)Tc, (210)Pb ((210)Po), (226)Ra, (228)Ra, (228)Th, (230)Th, (232)Th, (235)U, (238)U, (239)Pu and (240)Pu) are presented. The CRM can be used for Quality Assurance/Quality Control of analysis of radionuclides in seaweed and other biota samples, as well as for development and validation of analytical methods, and for training purposes. PMID:24291528

  18. Fundamental studies to develop certified reference material to calibrate spectrophotometer in the ultraviolet region

    NASA Astrophysics Data System (ADS)

    da Conceição, F. C.; Borges, P. P.; Gomes, J. F. S.

    2016-07-01

    Spectrophotometry is the technique used in a great number of laboratories around the world. Quantitative determination of a high number of inorganic, organic and biological species can be made by spectrophotometry using calibrated spectrophotometers. International standards require the use of optical filters to perform the calibration of spectrophotometers. One of the recommended materials is the crystalline potassium dichromate (K2Cr2O7), which is used to prepare solutions in specific concentrations for calibration or verification of spectrophotometers in the ultraviolet (UV) spectral regions. This paper presents the results concerning the fundamental studies for developing a certified reference material (CRM) of crystalline potassium dichromate to be used as standard of spectrophotometers in order to contribute to reliable quantitative analyses.

  19. Extending the soil moisture record of the climate reference network with machine learning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil moisture estimation is crucial for agricultural decision-support and a key component of hydrological and climatic research. Unfortunately, quality-controlled soil moisture time series data are uncommon before the most recent decade. However, time series data for precipitation are accessible at ...

  20. DEVELOPMENT OF TOXICITY REFERENCE VALUES FOR ECOLOGICAL SOIL SCREENING LEVELS (ECO-SSLS) FOR TERRESTRIAL WILDLIFE

    EPA Science Inventory

    Ecological Soil Screening Levels (Eco-SSLs) protective of terrestrial wildlife were developed by the USEPA Superfund. The wildlife Eco-SSL is the soil contaminant concentration where the Effect Dose (TRV) and Exposure Dose are equal (amount of contaminant in the diet that is take...

  1. Mica Mountain Muscovite: A New Silicate Hydrogen Isotope Standard Reference Material

    NASA Astrophysics Data System (ADS)

    Lonero, A.; Larson, P. B.; Neill, O. K.

    2015-12-01

    A new standard reference material consisting of finely ground muscovite flakes has been developed and utilized at Washington State University to calibrate hydrogen isotope ratio (D/H) measurements to the VSMOW scale. This standard was prepared from a single crystal 'book' of a muscovite-bearing pegmatite near Deary, ID. The value we obtained for this muscovite standard (MMM) is: δD VSMOW = -79.1 ± 2.0‰ relative to NBS-30 biotite at -65.7‰ compared to a VSMOW value of 0.00‰. This mean value was determined for the muscovite and has been used as our working standard. There have been many recent geological applications to continuous flow isotope ratio mass spectroscopy. When hydrogen isotope ratios are of interest, a suitable standard for hydrogen in silicate systems often is not available. With supplies of the older NBS-30 biotite standard exhausted, much D/H data measured on silicate minerals have been linked to the VSMOW scale via non-silicate reference materials which may not behave similarly to minerals under study. Some recent studies have shown the NBS-30 standard to have poor intra-laboratory agreement with that material's measured and accepted isotopic values (Qi et al., 2014). Many laboratories which would measure D/H in silicate minerals would benefit from using a silicate-based standard for hydrogen. With further characterization, this muscovite may also be useful as a standard for silicate oxygen ratios as well as for some major element cations. This muscovite standard gives consistent values and it is easy to work with and does not leave much combustion residue. Also, because muscovite contains little iron, metal-hydride formation and associated fractionation factors is greatly reduced during the sample combustion. A new silicate-hydrogen standard is needed by the community, and this work represents an example of what a replacement standard material could look like.

  2. Aflatoxin M1 in milk powders: processing, homogeneity and stability testing of certified reference materials.

    PubMed

    Josephs, R D; Ulberth, F; Van Egmond, H P; Emons, H

    2005-09-01

    As part of the certification campaign of three candidate reference materials for the determination of aflatoxin M1 (AfM1) in whole milk powders, homogeneity, short- and long-term stability tests of naturally contaminated milk powders have been performed. The homogeneity of two AfM1-contaminated milk powders was studied by taking samples at regular intervals of the filling sequences and analysing in triplicate for their AfM1 contents by liquid chromatography with fluorescence detection (LC-FLD) using random stratified sampling schemes. The homogeneity testing of an AfM1 'blank' milk powder material was performed by determining the nitrogen content because AfM1 levels were below the limit of detection of the most sensitive determination method. The short-term stability of AfM1-contaminated milk powders was evaluated at three different storage temperatures (4, 18 and 40 degrees C). After storage times of 0, 1, 2 and 4 weeks, samples were investigated using LC-FLD. The long-term stability study comprised of measurements after 0, 6, 12 and 18 months after storage at -20 and 4 degrees C. Analyses were done by LC-FLD. Based on the homogeneity tests, the materials were sufficiently homogenous to serve as certified reference materials. Corresponding uncertainty contributions of 0.23-0.89% were calculated for the homogeneity. The stability measurements showed no significant trends for both short- and long-term stability studies. The long-term stability uncertainties of the AfM1-contaminated milk powders were 7.4 and 6.3%, respectively, for a shelf-life of 6 years and storage at -20 degrees C. Supplementary stability monitoring schemes over a long period of several years are currently ongoing.

  3. Assessment of commutability for candidate certified reference material ERM-BB130 "chloramphenicol in pork".

    PubMed

    Zeleny, Reinhard; Emteborg, Håkan; Schimmel, Heinz

    2010-10-01

    Chloramphenicol (CAP), an effective antibiotic against many microorganisms, is meanwhile banned in the EU for treatment of food-producing animals due to adverse health effects. The Institute for Reference Materials and Measurements (IRMM) is currently developing a certified reference material (CRM) for CAP in pork, intended for validation and method performance verifications of analytical methods. The material will be certified using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) methods and has a target CAP level around the minimum required performance limit (MRPL) of 0.3 microg/kg. To prove that the material can be applied as a quality control tool for screening methods, a commutability study was conducted, involving five commercially available enzyme-linked immunosorbent assay kits and one biosensor assay (BiaCore kit). Meat homogenates (cryo-milled wet tissue) with CAP concentrations around the MRPL and the candidate CRM (lyophilised powder) were measured by LC-MS/MS and GC-MS as well as the six screening methods. Pairwise method comparisons of results obtained for the two sample types showed that the CRM can successfully be applied as quality control (QC) sample to all six screening methods. The study suggests that ERM-BB130 is sufficiently commutable with the investigated assays and that laboratories applying one of the investigated kits therefore benefit from using ERM-BB130 to demonstrate the correctness of their results. However, differences among the assays were observed, either in the abundance of bias between screening and confirmatory LC and GC methods, the repeatability of test results, or goodness of fit between the methods. PMID:20665007

  4. Review of remediation practices regarding cadmium-enriched farmland soil with particular reference to China.

    PubMed

    Tang, X; Li, Q; Wu, M; Lin, L; Scholz, M

    2016-10-01

    Cadmium-enrichment of farmland soil greatly threatens the sustainable use of soil resources and the safe cultivation of grain. This review paper briefly introduces the status of farmland soil as well as grain, which are both often polluted by cadmium (Cd) in China, and illustrates the major sources of Cd contaminants in farmland soil. In order to meet soil environmental quality standards and farmland environmental quality evaluation standards for edible agricultural products, Cd-enriched farmland soil is frequently remediated with the following prevailing techniques: dig and fill, electro-kinetic remediation, chemical elution, stabilisation and solidification, phytoremediation, field management and combined remediation. Most remediation techniques are still at the stage of small-scale trial experiments in China and few techniques are assessed in field trials. After comparing the technical and economical applicability among different Cd-enriched farmland soil remediation techniques, a novel ecological and hydraulic remediation technique has been proposed, which integrated the advantages of chemical elution, solidification and stabilisation, phytoremediation and field management. The ecological and hydraulic remediation concept is based on existing irrigation and drainage facilities, ecological ditches (ponds) and agronomic measures, which mainly detoxify the Cd-enriched soil during the interim period of crop cultivation, and guarantee the grain safety during its growth period. This technique may shift the challenge from soil to water treatment, and thus greatly enhances the remediation efficiency and shortens the remediation duration. Moreover, the proposed ecological and hydraulic remediation method matches well with the practical choice of cultivation while remediation for Cd-enriched soil in China, which has negligible impacts on the normal crop cultivation process, and thus shows great potential for large area applications. PMID:27562701

  5. Review of remediation practices regarding cadmium-enriched farmland soil with particular reference to China.

    PubMed

    Tang, X; Li, Q; Wu, M; Lin, L; Scholz, M

    2016-10-01

    Cadmium-enrichment of farmland soil greatly threatens the sustainable use of soil resources and the safe cultivation of grain. This review paper briefly introduces the status of farmland soil as well as grain, which are both often polluted by cadmium (Cd) in China, and illustrates the major sources of Cd contaminants in farmland soil. In order to meet soil environmental quality standards and farmland environmental quality evaluation standards for edible agricultural products, Cd-enriched farmland soil is frequently remediated with the following prevailing techniques: dig and fill, electro-kinetic remediation, chemical elution, stabilisation and solidification, phytoremediation, field management and combined remediation. Most remediation techniques are still at the stage of small-scale trial experiments in China and few techniques are assessed in field trials. After comparing the technical and economical applicability among different Cd-enriched farmland soil remediation techniques, a novel ecological and hydraulic remediation technique has been proposed, which integrated the advantages of chemical elution, solidification and stabilisation, phytoremediation and field management. The ecological and hydraulic remediation concept is based on existing irrigation and drainage facilities, ecological ditches (ponds) and agronomic measures, which mainly detoxify the Cd-enriched soil during the interim period of crop cultivation, and guarantee the grain safety during its growth period. This technique may shift the challenge from soil to water treatment, and thus greatly enhances the remediation efficiency and shortens the remediation duration. Moreover, the proposed ecological and hydraulic remediation method matches well with the practical choice of cultivation while remediation for Cd-enriched soil in China, which has negligible impacts on the normal crop cultivation process, and thus shows great potential for large area applications.

  6. Utilizing a reference material for assessing absolute tumor mechanical properties in modality independent elastography

    NASA Astrophysics Data System (ADS)

    Kim, Dong Kyu; Weis, Jared A.; Yankeelov, Thomas E.; Miga, Michael I.

    2014-03-01

    There is currently no reliable method for early characterization of breast cancer response to neoadjuvant chemotherapy (NAC) [1,2]. Given that disruption of normal structural architecture occurs in cancer-bearing tissue, we hypothesize that further structural changes occur in response to NAC. Consequently, we are investigating the use of modalityindependent elastography (MIE) [3-8] as a method for monitoring mechanical integrity to predict long term outcomes in NAC. Recently, we have utilized a Demons non-rigid image registration method that allows 3D elasticity reconstruction in abnormal tissue geometries, making it particularly amenable to the evaluation of breast cancer mechanical properties. While past work has reflected relative elasticity contrast ratios [3], this study improves upon that work by utilizing a known stiffness reference material within the reconstruction framework such that a stiffness map becomes an absolute measure. To test, a polyvinyl alcohol (PVA) cryogel phantom and a silicone rubber mock mouse tumor phantom were constructed with varying mechanical stiffness. Results showed that an absolute measure of stiffness could be obtained based on a reference value. This reference technique demonstrates the ability to generate accurate measurements of absolute stiffness to characterize response to NAC. These results support that `referenced MIE' has the potential to reliably differentiate absolute tumor stiffness with significant contrast from that of surrounding tissue. The use of referenced MIE to obtain absolute quantification of biomarkers is also translatable across length scales such that the characterization method is mechanics-consistent at the small animal and human application.

  7. Chemical analyses of soils and other surficial materials, Alaska

    USGS Publications Warehouse

    Gough, L.P.; Peard, J.L.; Severson, R.C.; Shacklette, H.T.; Thompkins, M.L.; Stewart, K.C.; Briggs, P.H.

    1984-01-01

    Introduction: The favorable response to the reports on the geochemistry of unconsolidated surficial materials of the conterminous United States (informally called the '50-mile geochemical survey,' Shacklette and others, 1971a, 1971b, 1973, and 1974) led us, in 1975, to initiate a somewhat similar survey of Alaska. The principal objective of studies of this type is to establish estimates of the abundance of elements in soils and other surficial materials. Such information is useful in the evaluation of geochemical data for (1) mineral resources, (2) environmental appraisals, and (3) the definition of broad-scale geochemical patterns. For about six years this effort progressed slowly on a non-funded, time-available basis. During fiscal years 1982 and 1983, however, some funds were made available through the USGS Energy Lands and Alaska Mineral Surveys programs which allowed for the completion of the field-work phase of the project. The sampling plan was kept simple because, as with the 50-mile study, the acquisition of samples depended on the voluntary cooperation of field personnel (only about 40 percent of the total number of samples was obtained by the authors).

  8. Accuracy of ELISA detection methods for gluten and reference materials: a realistic assessment.

    PubMed

    Diaz-Amigo, Carmen; Popping, Bert

    2013-06-19

    The determination of prolamins by ELISA and subsequent conversion of the resulting concentration to gluten content in food appears to be a comparatively simple and straightforward process with which many laboratories have years-long experience. At the end of the process, a value of gluten, expressed in mg/kg or ppm, is obtained. This value often is the basis for the decision if a product can be labeled gluten-free or not. On the basis of currently available scientific information, the accuracy of the obtained values with commonly used commercial ELISA kits has to be questioned. Although recently several multilaboratory studies have been conducted in an attempt to emphasize and ensure the accuracy of the results, data suggest that it was the precision of these assays, not the accuracy, that was confirmed because some of the underlying assumptions for calculating the gluten content lack scientific data support as well as appropriate reference materials for comparison. This paper discusses the issues of gluten determination and quantification with respect to antibody specificity, extraction procedures, reference materials, and their commutability.

  9. Soot Reference Materials for instrument calibration and intercomparisons: a workshop summary with recommendations

    NASA Astrophysics Data System (ADS)

    Baumgardner, D.; Popovicheva, O.; Allan, J.; Bernardoni, V.; Cao, J.; Cavalli, F.; Cozic, J.; Diapouli, E.; Eleftheriadis, K.; Genberg, P. J.; Gonzalez, C.; Gysel, M.; John, A.; Kirchstetter, T. W.; Kuhlbusch, T. A. J.; Laborde, M.; Lack, D.; Müller, T.; Niessner, R.; Petzold, A.; Piazzalunga, A.; Putaud, J. P.; Schwarz, J.; Sheridan, P.; Subramanian, R.; Swietlicki, E.; Valli, G.; Vecchi, R.; Viana, M.

    2012-03-01

    Soot, which is produced from biomass burning and the incomplete combustion of fossil and biomass fuels, has been linked to regional and global climate change and to negative health problems. Scientists measure soot using a variety of methods in order to quantify source emissions and understand its atmospheric chemistry, reactivity under emission conditions, interaction with solar radiation, influence on clouds, and health impacts. A major obstacle currently limiting progress is the absence of established standards or reference materials for calibrating the many instruments used to measure the various properties of soot. The current state of availability and practicability of soot standard reference materials (SRMs) was reviewed by a group of 50 international experts during a workshop in June of 2011. The workshop was convened to summarize the current knowledge on soot measurement techniques, identify the measurement uncertainties and limitations related to the lack of SRMs, and identify attributes of SRMs that, if developed, would reduce measurement uncertainties. The workshop established that suitable SRMs are available for calibrating some, but not all, measurement methods. The community of single-particle sootphotometer (SP2) users identified a suitable SRM, fullerene soot, but users of instruments that measure light absorption by soot collected on filters did not. Similarly, those who use thermal optical analysis (TOA) to analyze the organic and elemental carbon components of soot were not satisfied with current SRMs. The workshop produced recommendations for the development of new SRMs that would be suitable for the different soot measurement methods.

  10. Periodic reference tracking control approach for smart material actuators with complex hysteretic characteristics

    NASA Astrophysics Data System (ADS)

    Sun, Zhiyong; Hao, Lina; Song, Bo; Yang, Ruiguo; Cao, Ruimin; Cheng, Yu

    2016-10-01

    Micro/nano positioning technologies have been attractive for decades for their various applications in both industrial and scientific fields. The actuators employed in these technologies are typically smart material actuators, which possess inherent hysteresis that may cause systems behave unexpectedly. Periodic reference tracking capability is fundamental for apparatuses such as scanning probe microscope, which employs smart material actuators to generate periodic scanning motion. However, traditional controller such as PID method cannot guarantee accurate fast periodic scanning motion. To tackle this problem and to conduct practical implementation in digital devices, this paper proposes a novel control method named discrete extended unparallel Prandtl-Ishlinskii model based internal model (d-EUPI-IM) control approach. To tackle modeling uncertainties, the robust d-EUPI-IM control approach is investigated, and the associated sufficient stabilizing conditions are derived. The advantages of the proposed controller are: it is designed and represented in discrete form, thus practical for digital devices implementation; the extended unparallel Prandtl-Ishlinskii model can precisely represent forward/inverse complex hysteretic characteristics, thus can reduce modeling uncertainties and benefits controllers design; in addition, the internal model principle based control module can be utilized as a natural oscillator for tackling periodic references tracking problem. The proposed controller was verified through comparative experiments on a piezoelectric actuator platform, and convincing results have been achieved.

  11. Extensive sequencing of seven human genomes to characterize benchmark reference materials.

    PubMed

    Zook, Justin M; Catoe, David; McDaniel, Jennifer; Vang, Lindsay; Spies, Noah; Sidow, Arend; Weng, Ziming; Liu, Yuling; Mason, Christopher E; Alexander, Noah; Henaff, Elizabeth; McIntyre, Alexa B R; Chandramohan, Dhruva; Chen, Feng; Jaeger, Erich; Moshrefi, Ali; Pham, Khoa; Stedman, William; Liang, Tiffany; Saghbini, Michael; Dzakula, Zeljko; Hastie, Alex; Cao, Han; Deikus, Gintaras; Schadt, Eric; Sebra, Robert; Bashir, Ali; Truty, Rebecca M; Chang, Christopher C; Gulbahce, Natali; Zhao, Keyan; Ghosh, Srinka; Hyland, Fiona; Fu, Yutao; Chaisson, Mark; Xiao, Chunlin; Trow, Jonathan; Sherry, Stephen T; Zaranek, Alexander W; Ball, Madeleine; Bobe, Jason; Estep, Preston; Church, George M; Marks, Patrick; Kyriazopoulou-Panagiotopoulou, Sofia; Zheng, Grace X Y; Schnall-Levin, Michael; Ordonez, Heather S; Mudivarti, Patrice A; Giorda, Kristina; Sheng, Ying; Rypdal, Karoline Bjarnesdatter; Salit, Marc

    2016-06-07

    The Genome in a Bottle Consortium, hosted by the National Institute of Standards and Technology (NIST) is creating reference materials and data for human genome sequencing, as well as methods for genome comparison and benchmarking. Here, we describe a large, diverse set of sequencing data for seven human genomes; five are current or candidate NIST Reference Materials. The pilot genome, NA12878, has been released as NIST RM 8398. We also describe data from two Personal Genome Project trios, one of Ashkenazim Jewish ancestry and one of Chinese ancestry. The data come from 12 technologies: BioNano Genomics, Complete Genomics paired-end and LFR, Ion Proton exome, Oxford Nanopore, Pacific Biosciences, SOLiD, 10X Genomics GemCode WGS, and Illumina exome and WGS paired-end, mate-pair, and synthetic long reads. Cell lines, DNA, and data from these individuals are publicly available. Therefore, we expect these data to be useful for revealing novel information about the human genome and improving sequencing technologies, SNP, indel, and structural variant calling, and de novo assembly.

  12. Enantiomer fractions of polychlorinated biphenyls in three selected Standard Reference Materials.

    PubMed

    Morrissey, Joshua A; Bleackley, Derek S; Warner, Nicholas A; Wong, Charles S

    2007-01-01

    The enantiomer composition of six chiral polychlorinated biphenyls (PCBs) were measured in three different certified Standard Reference Materials (SRMs) from the US National Institute of Standards and Technology (NIST): SRM 1946 (Lake Superior fish tissue), SRM 1939a (PCB Congeners in Hudson River Sediment), and SRM 2978 (organic contaminants in mussel tissue--Raritan Bay, New Jersey) to aid in quality assurance/quality control methodologies in the study of chiral pollutants in sediments and biota. Enantiomer fractions (EFs) of PCBs 91, 95, 136, 149, 174, and 183 were measured using a suite of chiral columns by gas chromatography/mass spectrometry. Concentrations of target analytes were in agreement with certified values. Target analyte EFs in reference materials were measured precisely (<2% relative standard deviation), indicating the utility of SRM in quality assurance/control methodologies for analyses of chiral compounds in environmental samples. Measured EFs were also in agreement with previously published analyses of similar samples, indicating that similar enantioselective processes were taking place in these environmental matrices. PMID:16777177

  13. Extensive sequencing of seven human genomes to characterize benchmark reference materials.

    PubMed

    Zook, Justin M; Catoe, David; McDaniel, Jennifer; Vang, Lindsay; Spies, Noah; Sidow, Arend; Weng, Ziming; Liu, Yuling; Mason, Christopher E; Alexander, Noah; Henaff, Elizabeth; McIntyre, Alexa B R; Chandramohan, Dhruva; Chen, Feng; Jaeger, Erich; Moshrefi, Ali; Pham, Khoa; Stedman, William; Liang, Tiffany; Saghbini, Michael; Dzakula, Zeljko; Hastie, Alex; Cao, Han; Deikus, Gintaras; Schadt, Eric; Sebra, Robert; Bashir, Ali; Truty, Rebecca M; Chang, Christopher C; Gulbahce, Natali; Zhao, Keyan; Ghosh, Srinka; Hyland, Fiona; Fu, Yutao; Chaisson, Mark; Xiao, Chunlin; Trow, Jonathan; Sherry, Stephen T; Zaranek, Alexander W; Ball, Madeleine; Bobe, Jason; Estep, Preston; Church, George M; Marks, Patrick; Kyriazopoulou-Panagiotopoulou, Sofia; Zheng, Grace X Y; Schnall-Levin, Michael; Ordonez, Heather S; Mudivarti, Patrice A; Giorda, Kristina; Sheng, Ying; Rypdal, Karoline Bjarnesdatter; Salit, Marc

    2016-01-01

    The Genome in a Bottle Consortium, hosted by the National Institute of Standards and Technology (NIST) is creating reference materials and data for human genome sequencing, as well as methods for genome comparison and benchmarking. Here, we describe a large, diverse set of sequencing data for seven human genomes; five are current or candidate NIST Reference Materials. The pilot genome, NA12878, has been released as NIST RM 8398. We also describe data from two Personal Genome Project trios, one of Ashkenazim Jewish ancestry and one of Chinese ancestry. The data come from 12 technologies: BioNano Genomics, Complete Genomics paired-end and LFR, Ion Proton exome, Oxford Nanopore, Pacific Biosciences, SOLiD, 10X Genomics GemCode WGS, and Illumina exome and WGS paired-end, mate-pair, and synthetic long reads. Cell lines, DNA, and data from these individuals are publicly available. Therefore, we expect these data to be useful for revealing novel information about the human genome and improving sequencing technologies, SNP, indel, and structural variant calling, and de novo assembly. PMID:27271295

  14. Advances in Isotope Ratio Mass Spectrometry and Required Isotope Reference Materials

    PubMed Central

    Vogl, Jochen

    2013-01-01

    The article gives a condensed version of the keynote lecture held at the International Mass Spectrometry Conference 2012 in Kyoto. Starting with some examples for isotope research the key requirements for metrologically valid procedures enabling traceable and comparable isotope data are discussed. Of course multi-collector mass spectrometers are required which offer sufficiently high isotope ratio precision for the intended research work. Following this, corrections for mass fractionation/discrimination, validation of the analytical procedure including chemical sample preparation and complete uncertainty budgets are the most important issues for obtaining a metrologically valid procedure for isotope ratio determination. Only the application of such metrologically valid procedures enables the generation of traceable and comparable isotope data. To realize this suitable isotope and/or δ-reference materials are required, which currently are not sufficiently available for most isotope systems. Boron is given as an example, for which the situation regarding isotope and δ-reference materials is excellent. Boron may therefore serve as prototype for other isotope systems. PMID:24349939

  15. Determination of plutonium isotopes in seawater reference materials using isotope-dilution ICP-MS.

    PubMed

    Zheng, Jian; Yamada, Masatoshi

    2012-09-01

    We analyzed the activities of (239)Pu, (240)Pu, (239+240)Pu, (241)Pu, the ratio of number of atoms (atom ratio) for (240)Pu/(239)Pu, and the activity ratio of (241)Pu/(239+240)Pu in seawater reference materials, IAEA-443 and IAEA-381, using a highly sensitive isotope dilution sector field inductively coupled plasma mass spectrometry method. With a mean chemical yield of 65% determined with (242)Pu as a tracer, we found that the experimentally established values in IAEA-443 for (239)Pu, (240)Pu, (241)Pu and (239+240)Pu activities are almost the same as those in IAEA-381. Regarding the (239+240)Pu activity, we provided the most precise and accurate result among the twelve laboratories, which participated in the interlaboratory comparison. In addition, for the (240)Pu/(239)Pu atom ratio, our results for IAEA-381 (0.2315±0.0008) and IAEA-443 (0.2325±0.0008) are in good agreement with the IAEA information value (0.229±0.006), but have much smaller uncertainty. Since the new seawater reference material, IAEA-443, is commercially available, it can be used not only for method validation for seawater plutonium isotope ratio and activity analysis, but also for more general use as a plutonium isotope standard for mass discrimination correction for other environmental samples.

  16. Extensive sequencing of seven human genomes to characterize benchmark reference materials

    PubMed Central

    Zook, Justin M.; Catoe, David; McDaniel, Jennifer; Vang, Lindsay; Spies, Noah; Sidow, Arend; Weng, Ziming; Liu, Yuling; Mason, Christopher E.; Alexander, Noah; Henaff, Elizabeth; McIntyre, Alexa B.R.; Chandramohan, Dhruva; Chen, Feng; Jaeger, Erich; Moshrefi, Ali; Pham, Khoa; Stedman, William; Liang, Tiffany; Saghbini, Michael; Dzakula, Zeljko; Hastie, Alex; Cao, Han; Deikus, Gintaras; Schadt, Eric; Sebra, Robert; Bashir, Ali; Truty, Rebecca M.; Chang, Christopher C.; Gulbahce, Natali; Zhao, Keyan; Ghosh, Srinka; Hyland, Fiona; Fu, Yutao; Chaisson, Mark; Xiao, Chunlin; Trow, Jonathan; Sherry, Stephen T.; Zaranek, Alexander W.; Ball, Madeleine; Bobe, Jason; Estep, Preston; Church, George M.; Marks, Patrick; Kyriazopoulou-Panagiotopoulou, Sofia; Zheng, Grace X.Y.; Schnall-Levin, Michael; Ordonez, Heather S.; Mudivarti, Patrice A.; Giorda, Kristina; Sheng, Ying; Rypdal, Karoline Bjarnesdatter; Salit, Marc

    2016-01-01

    The Genome in a Bottle Consortium, hosted by the National Institute of Standards and Technology (NIST) is creating reference materials and data for human genome sequencing, as well as methods for genome comparison and benchmarking. Here, we describe a large, diverse set of sequencing data for seven human genomes; five are current or candidate NIST Reference Materials. The pilot genome, NA12878, has been released as NIST RM 8398. We also describe data from two Personal Genome Project trios, one of Ashkenazim Jewish ancestry and one of Chinese ancestry. The data come from 12 technologies: BioNano Genomics, Complete Genomics paired-end and LFR, Ion Proton exome, Oxford Nanopore, Pacific Biosciences, SOLiD, 10X Genomics GemCode WGS, and Illumina exome and WGS paired-end, mate-pair, and synthetic long reads. Cell lines, DNA, and data from these individuals are publicly available. Therefore, we expect these data to be useful for revealing novel information about the human genome and improving sequencing technologies, SNP, indel, and structural variant calling, and de novo assembly. PMID:27271295

  17. Modeling and Analysis of Scatterometry Signatures for Optical Critical Dimension Reference Material Applications

    NASA Astrophysics Data System (ADS)

    Patrick, Heather J.; Germer, Thomas A.; Cresswell, Michael W.; Allen, Richard A.; Dixson, Ronald G.; Bishop, Michael

    2007-09-01

    We use an optical critical dimension (OCD) technique, matching modeled to measured scatterometry signatures, to obtain critical dimension linewidth of lines in grating targets fabricated on SIMOX (separation by implantation of oxygen) substrates using the single-crystal critical dimension reference materials (SCCDRM) process. We first compare experimentally obtained reflectance signatures for areas of the unpatterned substrate with signatures modeled using Fresnel theory, and show that the buried oxide (BOX) layer of the SIMOX is not well described optically by a single homogeneous layer of SiO2, but can be so described if a mixed Si-SiO2 boundary layer is included between the Si wafer and the BOX layer. We then obtain linewidths from OCD measurements on a series of grating targets with a range of design linewidths and pitches, and show that the linewidth obtained from the OCD technique is linearly related to the linewidth obtained from scanning electron microscopy (SEM), with a slope near unity and zero offset. While these results are very promising, further work in improving the fit of the simulated signatures to the measured signatures for some of the targets, reducing the target line roughness, and analyzing the uncertainties for potential optical critical dimension reference materials, is anticipated.

  18. Production of NDA Working Reference Materials for the Capability Evaluation Project

    SciTech Connect

    Noll, P.D. Jr.; Marshall, R.S.

    1998-11-17

    The production of Non Destructive Assay (NDA) Working Reference Materials (WRMs) that are traceable to nationally recognized standards was undertaken to support implementation of the Idaho National Engineering and Environmental Laboratory (INEEL) Nondestructive Waste Assay Capability Evaluation Project (CEP). The WRMs produced for the CEP project consist of Increased Am/Pu mass ration (IAP) and depleted Uranium (DU) WRMs. The CEP IAP/DU WRM set provides radioactive material standards for use in combination with 55 gallon drum waste matrix surrogates for the assessment of waste NDA assay system performance. The Production of WRMs is a meticulous process that is not without certain trials and tribulations. Problems may arise at any of the various stages of WRM production which include, but are not limited to; material characterization (physical, chemical, and isotopic), material blend parameters, personnel radiation exposure, gas generation phenomenon, traceability to national standards, encapsulation, statistical evaluation of the data, and others. Presented here is an overall description of the process by which the CEP WRMs were produced and certified as well as discussions pertaining to some of the problems encountered and how they were solved.

  19. High concentration aqueous sodium fluoride certified reference materials for forensic use certified by complexometric titration.

    PubMed

    Archer, Marcellé; Brits, Martin; Prevoo-Franzsen, Désirée; Quinn, Laura

    2015-04-01

    Sodium fluoride in concentrations of 1 to 2 % is used to prevent the formation of ethanol in blood and urine samples that are to be analysed for ethanol content. The majority of such samples form part of forensic investigations into alleged drunken driving. In South Africa, the laboratory performing the tests is required to prove that the sodium fluoride concentration in the blood samples is above 1 g/100 ml on receipt. This is done by using a fluoride ion-selective electrode calibrated with external aqueous solutions of sodium fluoride. The National Metrology Institute of South Africa (NMISA) prepares sodium fluoride solutions in concentrations from 0.3 to 3.0 g/100 ml. No other certified sodium fluoride reference solutions in these concentrations are available commercially. The sodium fluoride is certified by precipitation of the fluoride as lead chlorofluoride (PbClF) through the addition of a known excess of lead nitrate. The excess lead is back-titrated with ethylenediamine tetraacetic acid (EDTA) using a photometric electrode to detect the endpoint. Aqueous sodium fluoride solutions are prepared and the concentrations verified by the precipitation/back-titration method. This paper shows the application of a classical complexometric method to the certification of reference materials and describes the procedures for the preparation of the sodium fluoride solutions, verification of the concentrations, homogeneity and stability by primary titrimetry. It also briefly covers the calculation of uncertainty, the establishment of traceability and the quality control measures applied to ensure the quality of the certified reference materials (CRMs). PMID:25326884

  20. High concentration aqueous sodium fluoride certified reference materials for forensic use certified by complexometric titration.

    PubMed

    Archer, Marcellé; Brits, Martin; Prevoo-Franzsen, Désirée; Quinn, Laura

    2015-04-01

    Sodium fluoride in concentrations of 1 to 2 % is used to prevent the formation of ethanol in blood and urine samples that are to be analysed for ethanol content. The majority of such samples form part of forensic investigations into alleged drunken driving. In South Africa, the laboratory performing the tests is required to prove that the sodium fluoride concentration in the blood samples is above 1 g/100 ml on receipt. This is done by using a fluoride ion-selective electrode calibrated with external aqueous solutions of sodium fluoride. The National Metrology Institute of South Africa (NMISA) prepares sodium fluoride solutions in concentrations from 0.3 to 3.0 g/100 ml. No other certified sodium fluoride reference solutions in these concentrations are available commercially. The sodium fluoride is certified by precipitation of the fluoride as lead chlorofluoride (PbClF) through the addition of a known excess of lead nitrate. The excess lead is back-titrated with ethylenediamine tetraacetic acid (EDTA) using a photometric electrode to detect the endpoint. Aqueous sodium fluoride solutions are prepared and the concentrations verified by the precipitation/back-titration method. This paper shows the application of a classical complexometric method to the certification of reference materials and describes the procedures for the preparation of the sodium fluoride solutions, verification of the concentrations, homogeneity and stability by primary titrimetry. It also briefly covers the calculation of uncertainty, the establishment of traceability and the quality control measures applied to ensure the quality of the certified reference materials (CRMs).

  1. Production of trace elements in coastal sea water certified reference material NMIA MX014.

    PubMed

    Merrick, Jeffrey P; Saxby, David L; White, Ian E A W; Antin, Luminita; Murby, E John

    2016-06-01

    A certified reference material (CRM) for trace elements in acidified sea water, NMIA MX014, has been produced by the National Measurement Institute Australia (NMIA). The CRM consists of natural coastal sea water with 12 elements (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se and V) fortified to levels relevant to environmental regulatory testing in Australia ranging from 0.4 to 22 μg/kg. Certified values for these 12 elements were assigned using reference methods developed at NMIA, using either isotope dilution or standard addition with ICP-MS measurement. Specialised sample preparation (coprecipitation) and ICP-MS optimisation (online dilution, collision/reaction chemistry, high mass resolution) were used to negate the effect of the high level of dissolved solids. Multiple confirmatory experiments were performed in order to verify that ICP-MS spectral interferences were eliminated and to estimate the measurement uncertainty contribution from method precision and method trueness. Extensive homogeneity and stability testing was performed and the measurement uncertainty of certified values includes contributions from between-bottle homogeneity, short-term stability, medium-term stability and long-term stability. Special attention was paid to the stability of Hg due to well-known preservation problems. Acidified sea water matrix was satisfactory for stabilising Hg at 0.4 μg/kg for at least 4 years. Relative expanded uncertainties (k = 2) for the 12 certified values were between 1 and 11 %. NMIA MX014 is intended for use as a reference material for analytical method validation and quality control for quantification of trace elements in saline water and other similar sample types. PMID:27108283

  2. Cadmium background concentrations to establish reference quality values for soils of São Paulo State, Brazil.

    PubMed

    de Oliveira, Vinicius Henrique; de Abreu, Cleide Aparecida; Coelho, Ricardo Marques; Melo, Leônidas Carrijo Azevedo

    2014-03-01

    Proper assessment of soil cadmium (Cd) concentrations is essential to establish legislative limits. The present study aimed to assess background Cd concentrations in soils from the state of São Paulo, Brazil, and to correlate such concentrations with several soil attributes. The topsoil samples (n = 191) were assessed for total Cd contents and for other metals using the USEPA 3051A method. The background concentration was determined according to the third quartile (75th). Principal component analysis, Spearman correlation, and multiple regressions between Cd contents and other soil attributes (pH, cation exchange capacity (CEC), clay content, sum of bases, organic matter, and total Fe, Al, Zn, and Pb levels) were performed. The mean Cd concentration of all 191 samples was 0.4 mg kg(-1), and the background concentration was 0.5 mg kg(-1). After the samples were grouped by parent material (rock origin) and soil type, the background Cd content varied, i.e., soils from igneous, metamorphic, and sedimentary rocks harbored 1.5, 0.4, and 0.2 mg kg(-1) of Cd, respectively. The background Cd content in Oxisols (0.8 mg kg(-1)) was higher than in Ultisols (0.3 mg kg(-1)). Multiple regression demonstrated that Fe was primarily attributed to the natural Cd contents in the soils (R (2) = 0.79). Instead of a single Cd background concentration value representing all São Paulo soils, we propose that the concentrations should be specific for at least Oxisols and Ultisols, which are the primary soil types.

  3. Cadmium background concentrations to establish reference quality values for soils of São Paulo State, Brazil.

    PubMed

    de Oliveira, Vinicius Henrique; de Abreu, Cleide Aparecida; Coelho, Ricardo Marques; Melo, Leônidas Carrijo Azevedo

    2014-03-01

    Proper assessment of soil cadmium (Cd) concentrations is essential to establish legislative limits. The present study aimed to assess background Cd concentrations in soils from the state of São Paulo, Brazil, and to correlate such concentrations with several soil attributes. The topsoil samples (n = 191) were assessed for total Cd contents and for other metals using the USEPA 3051A method. The background concentration was determined according to the third quartile (75th). Principal component analysis, Spearman correlation, and multiple regressions between Cd contents and other soil attributes (pH, cation exchange capacity (CEC), clay content, sum of bases, organic matter, and total Fe, Al, Zn, and Pb levels) were performed. The mean Cd concentration of all 191 samples was 0.4 mg kg(-1), and the background concentration was 0.5 mg kg(-1). After the samples were grouped by parent material (rock origin) and soil type, the background Cd content varied, i.e., soils from igneous, metamorphic, and sedimentary rocks harbored 1.5, 0.4, and 0.2 mg kg(-1) of Cd, respectively. The background Cd content in Oxisols (0.8 mg kg(-1)) was higher than in Ultisols (0.3 mg kg(-1)). Multiple regression demonstrated that Fe was primarily attributed to the natural Cd contents in the soils (R (2) = 0.79). Instead of a single Cd background concentration value representing all São Paulo soils, we propose that the concentrations should be specific for at least Oxisols and Ultisols, which are the primary soil types. PMID:24135921

  4. A technical review of the feasibility of producing certified reference materials for the measurement of gaseous pollutants in ambient air

    NASA Astrophysics Data System (ADS)

    Hafkenscheid, Theo; Baldan, Annarita; Quincey, Paul; Cortez, Leopoldo; Dias, Florbela; Brown, Richard H.; Wright, Mike; Gerboles, Michel; Saunders, Kevin

    Within the frame of the EU sponsored project 'Cermatair' (Certified Reference Materials for the Measurement of Gaseous Pollutants in Ambient Air, contract G6RD-CT-2001-00517) the feasibility of preparing and certifying reference materials for the measurement of sulphur dioxide, nitrogen dioxide, carbon monoxide and benzene in ambient air was studied. The project focused on measurements at concentration levels corresponding to limit values given in EU Ambient Air Quality Directives and covered reference materials for the reference methods specified in these Directives and for alternative methods based on diffusive sampling. State-of-the-art technologies for the production and certification of the reference materials were identified through literature surveys. Limited batches of reference materials were prepared and, wherever appropriate, tested for homogeneity. The reference materials were subsequently tested in small-scale external verifications, performed by 2-4 laboratories other than the preparation laboratory, aimed at identifying possible discrepancies between concentration values from the preparation processes and experimental values. The results of these verifications revealed possible mechanisms of certification (based on preparation or measurements). The remaining materials were subjected to a one-year stability study.

  5. Glass-based fluorescence reference materials used for optical and biophotonic applications

    NASA Astrophysics Data System (ADS)

    Engel, A.; Ottermann, C.; Resch-Genger, U.; Hoffmann, K.; Schweizer, S.; Selling, J.; Spaeth, J.-M.; Rupertus, V.

    2006-04-01

    Fluorescence techniques are known for their high sensitivity and are widely used as analytical tools and detection methods for product and process control, material sciences, environmental and biotechnical analysis, molecular genetics, cell biology, medical diagnostics, and drug screening. For routine measurements by fluorescence techniques the existence of an improved quality assurance is one of the basic needs. According to DIN/ISO 17025 certified standards are used for fluorescence diagnostics having the drawback of giving relative values only. Typical requirements onto fluorescence reference materials or standards deal with the verification of the instrument performance as well as the improvement of the data comparability. Especially for biomedical applications fluorescence labels are used for the detection of proteins. In particular these labels consist of nano crystalline materials like CdS and CdSe. The field of Non-Cadmium containing materials is under investigation. In order to evaluate whether glass based materials can be used as standards it is necessary to calculate absolute values like absorption/excitation cross sections or relative quantum yields. This can be done using different quantities of dopands in glass, glass ceramics or crystals. The investigated materials are based on different types of glass, silicate, phosphate and boron glass, which play a dominant role for the absorption and emission mechanism. Additional to the so-called elementary fluorescence properties induced by raw earth elements the formation of defects lead to higher cross sections additionally. The main investigations deal with wavelength accuracy and lifetime of doped glasses, glass ceramics and crystalline samples. Moreover intensity patterns, homogeneity aspects and photo stability will be discussed.

  6. Platinum stable isotope analysis of geological standard reference materials by double-spike MC-ICPMS

    PubMed Central

    Creech, J.B.; Baker, J.A.; Handler, M.R.; Bizzarro, M.

    2015-01-01

    We report a method for the chemical purification of Pt from geological materials by ion-exchange chromatography for subsequent Pt stable isotope analysis by multiple-collector inductively coupled plasma mass spectrometry (MC-ICPMS) using a 196Pt-198Pt double-spike to correct for instrumental mass bias. Double-spiking of samples was carried out prior to digestion and chemical separation to correct for any mass-dependent fractionation that may occur due to incomplete recovery of Pt. Samples were digested using a NiS fire assay method, which pre-concentrates Pt into a metallic bead that is readily dissolved in acid in preparation for anion-exchange chemistry. Pt was recovered from anion-exchange resin in concentrated HNO3 acid after elution of matrix elements, including the other platinum group elements (PGE), in dilute HCl and HNO3 acids. The separation method has been calibrated using a precious metal standard solution doped with a range of synthetic matrices and results in Pt yields of ≥90% with purity of ≥95%. Using this chemical separation technique, we have separated Pt from 11 international geological standard reference materials comprising of PGE ores, mantle rocks, igneous rocks and one sample from the Cretaceous–Paleogene boundary layer. Pt concentrations in these samples range from ca. 5 ng g−1 to 4 μg g−1. This analytical method has been shown to have an external reproducibility on δ198Pt (permil difference in the 198Pt/194Pt ratio from the IRMM-010 standard) of ±0.040 (2 sd) on Pt solution standards (Creech et al., 2013, J. Anal. At. Spectrom. 28, 853-865). The reproducibility in natural samples is evaluated by processing multiple replicates of four standard reference materials, and is conservatively taken to be ca. ±0.088 (2 sd). Pt stable isotope data for the full set of reference materials have a range of δ198Pt values with offsets of up to 0.4‰ from the IRMM-010 standard, which are readily resolved with this technique. These results

  7. Soils and Fertilizers. Competency Based Teaching Materials in Horticulture.

    ERIC Educational Resources Information Center

    Legacy, Jim; And Others

    This competency-based curriculum unit on soils and fertilizers is one of four developed for classroom use in teaching the turf and lawn services area of horticulture. The four sections are each divided into teaching content (in a question-and-answer format) and student skills that outline taking soil samples, testing samples, preparing soil for…

  8. Impact of carbonaceous materials in soil on the transport of soil-bound PAHs during rainfall-runoff events.

    PubMed

    Luo, Xiaolin; Zheng, Yi; Wu, Bin; Lin, Zhongrong; Han, Feng; Zhang, Wei; Wang, Xuejun

    2013-11-01

    Polycyclic Aromatic Hydrocarbons (PAHs) transported from contaminated soils by surface runoff pose significant risk for aquatic ecosystems. Based on a rainfall-runoff simulation experiment, this study investigated the impact of carbonaceous materials (CMs) in soil, identified by organic petrology analysis, on the transport of soil-bound PAHs under rainfall conditions. The hypothesis that composition of soil organic matter significantly impacts the enrichment and transport of PAHs was proved. CMs in soil, varying significantly in content, mobility and adsorption capacity, act differently on the transport of PAHs. Anthropogenic CMs like black carbon (BC) largely control the transport, as PAHs may be preferentially attached to them. Eventually, this study led to a rethink of the traditional enrichment theory. An important implication is that CMs in soil have to be explicitly considered to appropriately model the nonpoint source pollution of PAHs (possibly other hydrophobic chemicals as well) and assess its environmental risk.

  9. Element concentrations in soils and other surficial materials of Alaska

    USGS Publications Warehouse

    Gough, L.P.; Severson, R.C.; Shacklette, H.T.

    1988-01-01

    Mean concentrations of 35 elements, ash yields, and pH have been estimated for samples of sils and other unconsolidated surficial materials from 266 collection locations throughout Alaska. These background values can be applied to studies of environmental geochemistry and health, wildlife management, and soil-forming processes in cold climates and to computation of element abundances on a regional or worldwide scale. Limited data for an additoinal eight elements are also presented. Materials were collected using a one-way, three-level, analysis-of-variance samplling design in which collecting procedures were simplified for the convenience of the many volunteer field workers. The sample collectors were asked to avoid locations of known mineral deposits and obvious contamination, to take samples at a depth of about 20 cm where possible, and to take a replicate sample about 100 m distant from the first sample collected. With more than 60 percent of the samples replicated and 14 percent of the samples split for duplicate laboratory analyses, reliable estimates were made of the variability in element concentrations at two geographic scales and of the error associated with sample handling and laboratory procedures. Mean concentrations of most elements in surficial materials from the state of alaska correspond well with those reported in similar materials from the conterminous United STatess. Most element concentrations and ranges in samples of stream and lake sediments from Alaska, however, as reported in the literature, do not correspond well with those found in surficial materials of this study. This lack of correspondence is attributed to (1) a merger of two kinds ofsediments (stream and lake) for calculating means; (2) elimination from the sediment mean calculations of values below the limit of quantitative determination; (3) analytical methods different from those of the surficial materials study; and (4) most importantly, the inherent differences in chemistry of

  10. Passive Microwave Soil Moisture Retrieval through Combined Radar/Radiometer Ground Based Simulator with Special Reference to Dielectric Schemes

    NASA Astrophysics Data System (ADS)

    Srivastava, Prashant K., ,, Dr.; O'Neill, Peggy, ,, Dr.

    2014-05-01

    indicated a higher performance in terms of soil moisture retrieval accuracy for the Mironov dielectric model (RMSE of 0.035 m3/m3), followed by Dobson, Wang & Schmugge, and Hallikainen. This analysis indicates that Mironov dielectric model is promising for passive-only microwave soil moisture retrieval and could be a useful choice for SMAP satellite soil moisture retrieval. Keywords: Dielectric models; Single Channel Algorithm, Combined Radar/Radiometer, Soil moisture; L band References: Behari, J. (2005). Dielectric Behavior of Soil (pp. 22-40). Springer Netherlands O'Neill, P. E., Lang, R. H., Kurum, M., Utku, C., & Carver, K. R. (2006), Multi-Sensor Microwave Soil Moisture Remote Sensing: NASA's Combined Radar/Radiometer (ComRAD) System. In IEEE MicroRad, 2006 (pp. 50-54). IEEE. Srivastava, P. K., Han, D., Rico Ramirez, M. A., & Islam, T. (2013), Appraisal of SMOS soil moisture at a catchment scale in a temperate maritime climate. Journal of Hydrology, 498, 292-304. USDA OPE3 web site at http://www.ars.usda.gov/Research/.

  11. Review and evaluation of the effects of xenobiotic chemicals on microorganisms in soil. [139 references

    SciTech Connect

    Hicks, R.J.; Van Voris, P.

    1988-02-01

    The primary objective was to review and evaluate the relevance and quality of existing xenobiotic data bases and test methods for evaluating direct and indirect effects (both adverse and beneficial) of xenobiotics on the soil microbial community; direct and indirect effects of the soil microbial community on xenobiotics; and adequacy of test methods used to evaluate these effects and interactions. Xenobiotic chemicals are defined here as those compounds, both organic and inorganic, produced by man and introduced into the environment at concentrations that cause undesirable effects. Because soil serves as the main repository for many of these chemicals, it therefore has a major role in determining their ultimate fate. Once released, the distribution of xenobiotics between environmental compartments depends on the chemodynamic properties of the compounds, the physicochemical properties of the soils, and the transfer between soil-water and soil-air interfaces and across biological membranes. Abiotic and biotic processes can transform the chemical compound, thus altering its chemical state and, subsequently, its toxicity and reactivity. Ideally, the conversion is to carbon dioxide, water, and mineral elements, or at least, to some harmless substance. However, intermediate transformation products, which can become toxic pollutants in their own right, can sometimes be formed. 139 refs., 6 figs., 11 tabs.

  12. Laboratory-scale bioremediation of oil-contaminated soil of Kuwait with soil amendment materials.

    PubMed

    Cho, B H; Chino, H; Tsuji, H; Kunito, T; Nagaoka, K; Otsuka, S; Yamashita, K; Matsumoto, S; Oyaizu, H

    1997-10-01

    A huge amount of oil-contaminated soil remains unremediated in the Kuwait desert. The contaminated oil has the potentiality to cause pollution of underground water and to effect the health of people in the neighborhood. In this study, laboratory scale bioremediation experiments were carried out. Hyponex (Hyponex, Inc.) and bark manure were added as basic nutrients for microorganisms, and twelve kinds of materials (baked diatomite, microporous glass, coconut charcoal, an oil-decomposing bacterial mixture (Formula X from Oppenheimer, Inc.), and eight kinds of surfactants) were applied to accelerate the biodegradation of oil hydrocarbons. 15% to 33% of the contaminated oil was decomposed during 43 weeks' incubation. Among the materials tested, coconut charcoal enhanced the biodegradation. On the contrary, the addition of an oil-decomposing bacterial mixture impeded the biodegradation. The effects of the other materials were very slight. The toxicity of the biodegraded compounds was estimated by the Ames test and the tea pollen tube growth test. Both of the hydrophobic (dichloromethane extracts) and hydrophilic (methanol extracts) fractions showed a very slight toxicity in the Ames test. In the tea pollen tube growth test, the hydrophobic fraction was not toxic and enhanced the growth of pollen tubes.

  13. Laboratory-scale bioremediation of oil-contaminated soil of Kuwait with soil amendment materials.

    PubMed

    Cho, B H; Chino, H; Tsuji, H; Kunito, T; Nagaoka, K; Otsuka, S; Yamashita, K; Matsumoto, S; Oyaizu, H

    1997-10-01

    A huge amount of oil-contaminated soil remains unremediated in the Kuwait desert. The contaminated oil has the potentiality to cause pollution of underground water and to effect the health of people in the neighborhood. In this study, laboratory scale bioremediation experiments were carried out. Hyponex (Hyponex, Inc.) and bark manure were added as basic nutrients for microorganisms, and twelve kinds of materials (baked diatomite, microporous glass, coconut charcoal, an oil-decomposing bacterial mixture (Formula X from Oppenheimer, Inc.), and eight kinds of surfactants) were applied to accelerate the biodegradation of oil hydrocarbons. 15% to 33% of the contaminated oil was decomposed during 43 weeks' incubation. Among the materials tested, coconut charcoal enhanced the biodegradation. On the contrary, the addition of an oil-decomposing bacterial mixture impeded the biodegradation. The effects of the other materials were very slight. The toxicity of the biodegraded compounds was estimated by the Ames test and the tea pollen tube growth test. Both of the hydrophobic (dichloromethane extracts) and hydrophilic (methanol extracts) fractions showed a very slight toxicity in the Ames test. In the tea pollen tube growth test, the hydrophobic fraction was not toxic and enhanced the growth of pollen tubes. PMID:9314191

  14. Microbial properties of mine spoil materials in the initial stages of soil development

    SciTech Connect

    Machulla, G.; Bruns, M.A.; Scow, K.M.

    2005-08-01

    The early years of soil genesis during mine spoil reclamation are critical for vegetative establishment and may help predict reclamation success. Mine spoils in the Halle-Leipzig region of Germany were analyzed for microbial changes following a hay mulch-seeding treatment without topsoil or fertilizer application. Microbial biomass carbon (C{sub mic}) and dehydrogenase activity (DHA) of spoils were measured each year in the first 3 yr after treatment. In the third year, bacterial community DNA fingerprints were compared with those from a reference soil. Microbial indicators were measured at three depths in the upper 10 cm of spoils at three sites with contrasting parent materials: glacial till (sandy loam), limnic tertiary sediments (high-lignite sandy clay loam), and quaternary sand and gravel (loamy sand). Before reclamation, C{sub mic} means and standard deviations of surface spoils (0-1 cm) were 9{+-}6, 39{+-}11, and 38{+-}16 mg kg{sup -1} for the loamy sand, high-lignite sandy clay loam, and sandy loam spoils, respectively. Within one year, mean C{sub mic} at the surface increased to 148{+-}70, 229{+-}64, and 497{+-}167 mg kg{sup -1}, respectively, and was significantly higher at 0 to 1 cm than at lower depths. Highest DHA and DNA yields were obtained in the 0- to 1-cm depth of the sandy loam spoils. Microbial biomass C values exhibited significant correlations with DHA, DNA yield, and extractable C for all three mine spoils. Soil microbial indices were more responsive than plant measurements to differences in parent materials.

  15. Applying a new procedure to assess the controls on aggregate stability - including soil parent material and soil organic carbon concentrations - at the landscape scale

    NASA Astrophysics Data System (ADS)

    Turner, Gren; Rawlins, Barry; Wragg, Joanna; Lark, Murray

    2014-05-01

    Aggregate stability is an important physical indicator of soil quality and influences the potential for erosive losses from the landscape, so methods are required to measure it rapidly and cost-effectively. Previously we demonstrated a novel method for quantifying the stability of soil aggregates using a laser granulometer (Rawlins et al., 2012). We have developed our method further to mimic field conditions more closely by incorporating a procedure for pre-wetting aggregates (for 30 minutes on a filter paper) prior to applying the test. The first measurement of particle-size distribution is made on the water stable aggregates after these have been added to circulating water (aggregate size range 1000 to 2000 µm). The second measurement is made on the disaggregated material after the circulating aggregates have been disrupted with ultrasound (sonication). We then compute the difference between the mean weight diameters (MWD) of these two size distributions; we refer to this value as the disaggregation reduction (DR; µm). Soils with more stable aggregates, which are resistant to both slaking and mechanical breakdown by the hydrodynamic forces during circulation, have larger values of DR. We made repeated analyses of DR using an aggregate reference material (RM; a paleosol with well-characterised disaggregation properties) and used this throughout our analyses to demonstrate our approach was reproducible. We applied our modified technique - and also the previous technique in which dry aggregates were used - to a set of 60 topsoil samples (depth 0-15 cm) from cultivated land across a large region (10 000 km2) of eastern England. We wished to investigate: (i) any differences in aggregate stability (DR measurements) using dry or pre-wet aggregates, and (ii) the dominant controls on the stability of aggregates in water using wet aggregates, including variations in mineralogy and soil organic carbon (SOC) content, and any interaction between them. The sixty soil

  16. Soil bacterial communities of a calcium-supplemented and a reference watershed at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA.

    PubMed

    Sridevi, Ganapathi; Minocha, Rakesh; Turlapati, Swathi A; Goldfarb, Katherine C; Brodie, Eoin L; Tisa, Louis S; Minocha, Subhash C

    2012-03-01

    Soil Ca depletion because of acidic deposition-related soil chemistry changes has led to the decline of forest productivity and carbon sequestration in the northeastern USA. In 1999, acidic watershed (WS) 1 at the Hubbard Brook Experimental Forest (HBEF), NH, USA was amended with Ca silicate to restore soil Ca pools. In 2006, soil samples were collected from the Ca-amended (WS1) and reference watershed (WS3) for comparison of bacterial community composition between the two watersheds. The sites were about 125 m apart and were known to have similar stream chemistry and tree populations before Ca amendment. Ca-amended soil had higher Ca and P, and lower Al and acidity as compared with the reference soils. Analysis of bacterial populations by PhyloChip revealed that the bacterial community structure in the Ca-amended and the reference soils was significantly different and that the differences were more pronounced in the mineral soils. Overall, the relative abundance of 300 taxa was significantly affected. Numbers of detectable taxa in families such as Acidobacteriaceae, Comamonadaceae, and Pseudomonadaceae were lower in the Ca-amended soils, while Flavobacteriaceae and Geobacteraceae were higher. The other functionally important groups, e.g. ammonia-oxidizing Nitrosomonadaceae, had lower numbers of taxa in the Ca-amended organic soil but higher in the mineral soil.

  17. A mussel (Mytilus edulis) tissue certified reference material for the marine biotoxins azaspiracids.

    PubMed

    McCarron, Pearse; Giddings, Sabrina D; Reeves, Kelley L; Hess, Philipp; Quilliam, Michael A

    2015-04-01

    Azaspiracids (AZAs) are lipophilic biotoxins produced by marine algae that can contaminate shellfish and cause human illness. The European Union (EU) regulates the level of AZAs in shellfish destined for the commercial market, with liquid chromatography-mass spectrometry (LC-MS) being used as the official reference method for regulatory analysis. Certified reference materials (CRMs) are essential tools for the development, validation, and quality control of LC-MS methods. This paper describes the work that went into the planning, preparation, characterization, and certification of CRM-AZA-Mus, a tissue matrix CRM, which was prepared as a wet homogenate from mussels (Mytilus edulis) naturally contaminated with AZAs. The homogeneity and stability of CRM-AZA-Mus were evaluated, and the CRM was found to be fit for purpose. Extraction and LC-MS/MS methods were developed to accurately certify the concentrations of AZA1 (1.16 mg/kg), AZA2 (0.27 mg/kg), and AZA3 (0.21 mg/kg) in the CRM. Quantitation methods based on standard addition and matrix-matched calibration were used to compensate for the matrix effects in LC-MS/MS. Other toxins present in this CRM at lower levels were also measured with information values reported for okadaic acid, dinophysistoxin-2, yessotoxin, and several spirolides.

  18. Building a Library Collection on Visual and Physical Disabilities: Basic Materials and Resources. Reference Circular No. 99-01.

    ERIC Educational Resources Information Center

    Library of Congress, Washington, DC. National Library Service for the Blind and Physically Handicapped.

    The materials included in this reference circular are recommended as basic resources for providing current information on general aspects of visual impairments and physical disabilities. The selections, based on the holdings of the Reference Section, National Library Service for the Blind and Physically Handicapped (NLS), were chosen for their…

  19. Reference Material for Radionuclides in Sediment, IAEA-384 (Fangataufa Lagoon Sediment)

    SciTech Connect

    Povinec, P; Pham, M; Barci-Funel, G; Bojanawski, R; Boshkova, T; Burnett, W; Carvalho, F; Chapeyron, B; Cunha, I; Dahlgaard, H; Galabov, N; Gastaud, J; Geering, J; Gomez, I; Green, N; Hamilton, T; Ibanez, F; Majah, M I; John, M; Kanisch, G; Kenna, T; Kloster, M; Korun, M; Wee Kwong, L L; La Rosa, J; Lee, S; Levy-Palomo, I; Malatova, M; Maruo, Y; Mitchell, P; Murciano, I; Nelson, R; Oh, J; Oregioni, B; Petit, G L; Pettersson, H; Reineking, A; Smedley, P; Suckow, A; der Struijs, T v; Voors, P; Yoshimizu, K; Wyse, E

    2005-09-23

    The IAEA Marine Environment Laboratory (IAEA-MEL) in Monaco has conducted intercomparison exercises on radionuclides in marine samples for many years as part of its contribution to the IAEA's program of Analytical Quality Control Services (AQCS). An important part of the AQCS program has been a production of Reference Materials (RMs) and their provision to radioanalytical laboratories. The RMs have been developed for different marine matrices (sediment, water, biota), with accuracy and precision required for the present state of the art of radiometrics and mass spectrometry methods. The RMs have been produced as the final products of world-wide intercomparison exercises organized during last 30 years. A total of 44 intercomparison exercises were undertaken and 39 RMs were produced for radionuclides in the marine environment. All required matrices (seawater, biota, sediment) have been covered with radionuclide concentrations ranging from typical environmental levels to elevated levels affected by discharges from nuclear reprocessing plants. The long-term availability of RMs (over 10 years) requires the use of very specific techniques to collect and pretreat large quantities of material (e.g., in excess of 100 kg) in order to ensure sample stability and homogenization of any analytes of interest. The production of a RM is therefore a long process, covering the identification of needs, sample collection, pre-treatment, homogenization, bottling, distribution to laboratories, evaluation of data, preliminary reporting, additional analyses in expert laboratories, certification of the material, and finally issuing the RM. In this paper we describe a reference material IAEA-384, Fangataufa lagoon sediment, designed for determination of anthropogenic and natural radionuclides in the marine environment. This RM has been prepared with the aim of testing the performance of analytical laboratories to measure the activity of these radionuclides in a sediment sample contaminated

  20. Soot reference materials for instrument calibration and intercomparisons: a workshop summary with recommendations

    NASA Astrophysics Data System (ADS)

    Baumgardner, D.; Popovicheva, O.; Allan, J.; Bernardoni, V.; Cao, J.; Cavalli, F.; Cozic, J.; Diapouli, E.; Eleftheriadis, K.; Genberg, P. J.; Gonzalez, C.; Gysel, M.; John, A.; Kirchstetter, T. W.; Kuhlbusch, T. A. J.; Laborde, M.; Lack, D.; Müller, T.; Niessner, R.; Petzold, A.; Piazzalunga, A.; Putaud, J. P.; Schwarz, J.; Sheridan, P.; Subramanian, R.; Swietlicki, E.; Valli, G.; Vecchi, R.; Viana, M.

    2012-08-01

    Soot, which is produced from biomass burning and the incomplete combustion of fossil and biomass fuels, has been linked to regional and global climate change and to negative health problems. Scientists measure the properties of soot using a variety of methods in order to quantify source emissions and understand its atmospheric chemistry, reactivity under emission conditions, interaction with solar radiation, influence on clouds, and health impacts. A major obstacle currently limiting progress is the absence of established standards or reference materials for calibrating the many instruments used to measure the various properties of soot. The current state of availability and practicability of soot standard reference materials (SRMs) was reviewed by a group of 50 international experts during a workshop in June of 2011. The workshop was convened to summarize the current knowledge on soot measurement techniques, identify the measurement uncertainties and limitations related to the lack of soot SRMs, and identify attributes of SRMs that, if developed, would reduce measurement uncertainties. The workshop established that suitable SRMs are available for calibrating some, but not all, measurement methods. The community of users of the single-particle soot-photometer (SP2), an instrument using laser-induced incandescence, identified a suitable SRM, fullerene soot, but users of instruments that measure light absorption by soot collected on filters did not. Similarly, those who use thermal optical analysis (TOA) to analyze the organic and elemental carbon components of soot were not satisfied with current SRMs. The workshop, and subsequent, interactive discussions, produced a number of recommendations for the development of new SRMs, and their implementation, that would be suitable for the different soot measurement methods.

  1. T-2 and HT-2 toxins in oat flakes: development of a certified reference material.

    PubMed

    Köppen, Robert; Bremser, Wolfram; Stephan, Ina; Klein-Hartwig, Karin; Rasenko, Tatjana; Koch, Matthias

    2015-04-01

    Trichothecene mycotoxins, with T-2 and HT-2 toxins being the main representatives of the type A subgroup, are naturally and worldwide occurring contaminants frequently found in grain-based food and feed. Due to the high consumption of these products and the potential health risk associated herewith, concerns about the safety and quality of food and feed have increased over the last decades at both governmental and consumer levels. Since it is not possible to avoid their occurrence, tremendous efforts have been performed to identify and monitor mycotoxins in food and feed to make their consumption safe. However, suitable certified reference materials (CRMs) intended for quality assurance and quality control purposes are still lacking for many mycotoxin-matrix combinations. Therefore, in the framework of a European Reference Material (ERM®) project, the first CRM for T-2 and HT-2 toxin in ground oat flakes (ERM®-BC720) was developed according to the requirements of ISO Guide 35. The whole process of ERM®-BC720 development, including sample preparation, homogeneity and stability studies and value assignment, is presented. The assignment of the certified mass fractions was based upon an in-house study using high-performance liquid chromatography isotope-dilution tandem mass spectrometry. Simultaneously, an interlaboratory comparison study involving 24 expert laboratories was conducted in order to support the in-house certification study. The certified values and their corresponding expanded uncertainties (k = 2) for both T-2 and HT-2 toxin in ERM®-BC720, traceable to the international system of units, are (82 ± 4) μg kg(-1) and (81 ± 4) μg kg(-1), respectively.

  2. Palm-Based Standard Reference Materials for Iodine Value and Slip Melting Point

    PubMed Central

    Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai; Kuntom, Ainie

    2008-01-01

    This work described study protocols on the production of Palm-Based Standard Reference Materials for iodine value and slip melting point. Thirty-three laboratories collaborated in the inter-laboratory proficiency tests for characterization of iodine value, while thirty-two laboratories for characterization of slip melting point. The iodine value and slip melting point of palm oil, palm olein and palm stearin were determined in accordance to MPOB Test Methods p3.2:2004 and p4.2:2004, respectively. The consensus values and their uncertainties were based on the acceptability of statistical agreement of results obtained from collaborating laboratories. The consensus values and uncertainties for iodine values were 52.63 ± 0.14 Wijs in palm oil, 56.77 ± 0.12 Wijs in palm olein and 33.76 ± 0.18 Wijs in palm stearin. For the slip melting points, the consensus values and uncertainties were 35.6 ± 0.3 °C in palm oil, 22.7 ± 0.4 °C in palm olein and 53.4 ± 0.2 °C in palm stearin. Repeatability and reproducibility relative standard deviations were found to be good and acceptable, with values much lower than that of 10%. Stability of Palm-Based Standard Reference Materials remained stable at temperatures of −20 °C, 0 °C, 6 °C and 24 °C upon storage for one year. PMID:19609396

  3. T-2 and HT-2 toxins in oat flakes: development of a certified reference material.

    PubMed

    Köppen, Robert; Bremser, Wolfram; Stephan, Ina; Klein-Hartwig, Karin; Rasenko, Tatjana; Koch, Matthias

    2015-04-01

    Trichothecene mycotoxins, with T-2 and HT-2 toxins being the main representatives of the type A subgroup, are naturally and worldwide occurring contaminants frequently found in grain-based food and feed. Due to the high consumption of these products and the potential health risk associated herewith, concerns about the safety and quality of food and feed have increased over the last decades at both governmental and consumer levels. Since it is not possible to avoid their occurrence, tremendous efforts have been performed to identify and monitor mycotoxins in food and feed to make their consumption safe. However, suitable certified reference materials (CRMs) intended for quality assurance and quality control purposes are still lacking for many mycotoxin-matrix combinations. Therefore, in the framework of a European Reference Material (ERM®) project, the first CRM for T-2 and HT-2 toxin in ground oat flakes (ERM®-BC720) was developed according to the requirements of ISO Guide 35. The whole process of ERM®-BC720 development, including sample preparation, homogeneity and stability studies and value assignment, is presented. The assignment of the certified mass fractions was based upon an in-house study using high-performance liquid chromatography isotope-dilution tandem mass spectrometry. Simultaneously, an interlaboratory comparison study involving 24 expert laboratories was conducted in order to support the in-house certification study. The certified values and their corresponding expanded uncertainties (k = 2) for both T-2 and HT-2 toxin in ERM®-BC720, traceable to the international system of units, are (82 ± 4) μg kg(-1) and (81 ± 4) μg kg(-1), respectively. PMID:25399074

  4. Characterization of Perchlorate in a New Frozen Human Urine Standard Reference Material

    PubMed Central

    Yu, Lee L.; Jarrett, Jeffery M.; Davis, W. Clay; Kilpatrick, Eric L.; Oflaz, Rabia; Turk, Gregory C.; Leber, Dennis D.; Valentin, Liza; Morel-Espinosa, Maria; Blount, Benjamin C.

    2015-01-01

    Perchlorate, an inorganic anion, has recently been recognized as an environmental contaminant by the U.S. Environmental Protection Agency (EPA). Urine is the preferred matrix for assessment of human exposure to perchlorate. Although the measurement technique for perchlorate in urine was developed in 2005, the calibration and quality assurance aspects of the metrology infrastructure for perchlorate are still lacking in that there is no certified reference material (CRM) traceable to the International System of Units (SI). To meet the quality assurance needs in biomonitoring measurements of perchlorate and the related anions that affect thyroid health, the National Institute of Standards and Technology (NIST) in collaboration with the Centers for Disease Control and Prevention (CDC) developed Standard Reference Material (SRM) 3668 Mercury, Perchlorate, and Iodide in Frozen Human Urine. SRM 3668 consists of perchlorate, nitrate, thiocyanate, iodine, and mercury in urine at two levels that represent the 50th and 95th percentiles, respectively, of the concentrations (with some adjustments) in the U.S. population. It is the first CRM being certified for perchlorate. Measurements leading to the certification of perchlorate were made collaboratively at NIST and CDC using three methods based on liquid or ion chromatography tandem mass spectrometry (LC-MS/MS or IC-MS/MS). Potential sources of bias were analyzed and results were compared for the three methods. Perchlorate in SRM 3668 Level I urine was certified to be 2.70 μg L−1 ± 0.21 μg L−1, and for SRM 3668 Level II urine, the certified value is 13.47 μg L−1 ± 0.96 μg L−1. PMID:22850897

  5. Feasibility study on production of a matrix reference material for cyanobacterial toxins.

    PubMed

    Hollingdale, Christie; Thomas, Krista; Lewis, Nancy; Békri, Khalida; McCarron, Pearse; Quilliam, Michael A

    2015-07-01

    The worldwide increase in cyanobacterial contamination of freshwater lakes and rivers is of great concern as many cyanobacteria produce potent hepatotoxins and neurotoxins (cyanotoxins). Such toxins pose a threat to aquatic ecosystems, livestock, and drinking water supplies. In addition, dietary supplements prepared from cyanobacteria can pose a risk to consumers if they contain toxins. Analytical monitoring for toxins in the environment and in consumer products is essential for the protection of public health. Reference materials (RMs) are an essential tool for the development and validation of analytical methods and are necessary for ongoing quality control of monitoring operations. Since the availability of appropriate RMs for cyanotoxins has been very limited, the present study was undertaken to examine the feasibility of producing a cyanobacterial matrix RM containing various cyanotoxins. The first step was large-scale culturing of various cyanobacterial cultures that produce anatoxins, microcystins, and cylindrospermopsins. After harvesting, the biomass was lyophilized, blended, homogenized, milled, and bottled. The moisture content and physical characteristics were assessed in order to evaluate the effectiveness of the production process. Toxin levels were measured by liquid chromatography with tandem mass spectrometry and ultraviolet detection. The reference material was found to be homogeneous for toxin content. Stability studies showed no significant degradation of target toxins over a period of 310 days at temperatures up to +40 °C except for the anatoxin-a, which showed some degradation at +40 °C. These results show that a fit-for-purpose matrix RM for cyanotoxins can be prepared using the processes and techniques applied in this work.

  6. Advances in Huntington's disease diagnostics: development of a standard reference material.

    PubMed

    Levin, Barbara C; Richie, Kristy L; Jakupciak, John P

    2006-07-01

    Huntington's disease (HD) is a neurodegenerative disease that affects four to seven individuals per 100,000. The onset of symptoms usually begins in middle age, although approximately 5% become symptomatic as juveniles. Death occurs approximately 15 years following the onset of symptoms, which include choreic movements, cognitive decline and psychiatric changes. HD is an autosomal dominant inherited disease that is associated with an expansion of a trinucleotide (CAG) repeat located on chromosome 4. Physicians rely on a positive family history, and diagnostic and genetic tests to detect the expansion in the number of CAG trinucleotide repeats in the HD gene to confirm the diagnosis. More than 99% of HD patients have 40 or more CAG triplet repeats and, therefore, targeted mutational analysis is greater than 99% sensitive. Individuals with 26 triplet repeats or less are normal, and while those with 27-35 repeats may not demonstrate symptoms themselves, their offspring may have the disease. Individuals with 36-39 repeats may or may not exhibit symptoms. The College of American Pathology/American College of Medical Genetics Biochemical and Molecular Genetics Resource Committee has emphasized the need to standardize the methodology for the determination of the accurate number of CAG repeats. This will prevent false-positive or -negative results when conducting predictive or prenatal testing of at-risk individuals. The National Institute of Standards and Technology is developing a standard reference material to provide these positive and negative controls needed by clinical testing laboratories. The use of a HD standard reference material will provide the quality control and assurance that data from different laboratories are both comparable and accurate.

  7. Effect of Polycyclic Aromatic Hydrocarbon Source Materials and Soil Components on Partitioning and Dermal Uptake.

    PubMed

    Xia, Huan; Gomez-Eyles, Jose L; Ghosh, Upal

    2016-04-01

    The bioavailability of polycyclic aromatic hydrocarbons (PAHs) in soils can be influenced by the source material they are emitted within, the properties of the receiving soil, weathering processes, and the concentration of PAHs. In this study 30 contaminated soils were constructed with common PAH sources (fuel oil, soot, coal tar based skeet particles) and direct spike with a solvent added to different types and contents of soil organic matter and minerals to achieve PAH concentrations spanning 4 orders of magnitude. Source material had the greatest impact on PAH partitioning. Soils containing skeet generally exhibited the highest KD values, followed by soot, fuel oil, and solvent spiked soils. Among all soil compositions, the presence of 2% charcoal had the largest enhancement of KD. Partitioning behavior could not be predicted by an organic carbon and black carbon partitioning model. Including independently measured partitioning behavior of the soil components and PAH sources allowed better prediction but still suffered from issues of interaction (oil sorption in peat) and highly nonlinear partitioning with depletion (for skeet). Dermal absorption of PAHs measured using pig skin was directly related to the freely dissolved aqueous concentration in soil and not the total concentration in the soil. Overall, we show that PAH source materials have a dominating influence on partitioning, highlighting the importance of using native field soils in bioavailability and risk assessments. PMID:26964018

  8. [Effects of Different Kinds of Organic Materials on Soil Heavy Metal Phytoremediation Efficiency by Sedum alfredii Hance].

    PubMed

    Yao, Gui-hua; Xu, Hai-zhou; Zhu, Lin-gang; Ma, Jia-wei; Liu, Dan; Ye, Zheng-qian

    2015-11-01

    In this study, a pot experiment was conducted to investigate the effect of clean organic materials i. e., biogas residue (BR), mushroom residue (MR), and bamboo shell (BS) on phytoextraction remediation of two heavy metal contaminated soils (collected from Wenzhou and Fuyang, which referred to "Wenzhou soil" and "Fuyang soil", respectively.) using a cadmium (Cd) and zinc (Zn) hyperaccumulator Sedum alfredii Hance. The results indicated that the effects of organic materials on availabilities of soil heavy metals were different due to different kinds of heavy metals, organic materials, and the application rates of the organic materials. Addition with 5% BR showed the greatest activation to copper (Cu), Zn in Wenzhou soil, and in Fuyang soil 1% BS had the highest activation for Cu, Zn, lead ( Ph) and Cd. Growth of shoot biomass of Sedum alfredii Hance increased with the addition rate of organic materials, and the plant dry weights were increased by 23.7%-93.0%. In Wenzhou soil, only 1% BS treatment had the best effect on Cd uptake and accumulation in shoots of Sedum alfredii Hance, increased by 22.6%, while other treatments were inferior to the control. For Zn, MR treatments were inferior to the control, while other treafments were superior to the control, of which 5% BR, 1% BS and 5% BS exceeded the control by 39. 6%, 32.6% and 23.8%, respectively. In Fuyang soil, for Cd, the treatment effects of 5% BS, 1% BR and 5% BR were the greatest, of which Cd accumulation in shoots exceeded the control by 12.9%, 12.8% and 6.2%, respectively, while Cd accumulations in shoots in all other treatments were less than that of control. For Zn, the treatments of adding organic materials promoted Zn accumulation in shoots of Sedum alfredii Hance, and the best treatments were as follows: 5% BS. 5% BR and 5% MR, exceeded the control by 38.4%, 25.7% and 22.4%, respectively. PMID:26911018

  9. Milk and serum standard reference materials for monitoring organic contaminants in human samples.

    PubMed

    Schantz, Michele M; Eppe, Gauthier; Focant, Jean-François; Hamilton, Coreen; Heckert, N Alan; Heltsley, Rebecca M; Hoover, Dale; Keller, Jennifer M; Leigh, Stefan D; Patterson, Donald G; Pintar, Adam L; Sharpless, Katherine E; Sjödin, Andreas; Turner, Wayman E; Vander Pol, Stacy S; Wise, Stephen A

    2013-02-01

    Four new Standard Reference Materials (SRMs) have been developed to assist in the quality assurance of chemical contaminant measurements required for human biomonitoring studies, SRM 1953 Organic Contaminants in Non-Fortified Human Milk, SRM 1954 Organic Contaminants in Fortified Human Milk, SRM 1957 Organic Contaminants in Non-Fortified Human Serum, and SRM 1958 Organic Contaminants in Fortified Human Serum. These materials were developed as part of a collaboration between the National Institute of Standards and Technology (NIST) and the Centers for Disease Control and Prevention (CDC) with both agencies contributing data used in the certification of mass fraction values for a wide range of organic contaminants including polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, polybrominated diphenyl ether (PBDE) congeners, and polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners. The certified mass fractions of the organic contaminants in unfortified samples, SRM 1953 and SRM 1957, ranged from 12 ng/kg to 2200 ng/kg with the exception of 4,4'-DDE in SRM 1953 at 7400 ng/kg with expanded uncertainties generally <14 %. This agreement suggests that there were no significant biases existing among the multiple methods used for analysis. PMID:23132544

  10. Milk and serum standard reference materials for monitoring organic contaminants in human samples.

    PubMed

    Schantz, Michele M; Eppe, Gauthier; Focant, Jean-François; Hamilton, Coreen; Heckert, N Alan; Heltsley, Rebecca M; Hoover, Dale; Keller, Jennifer M; Leigh, Stefan D; Patterson, Donald G; Pintar, Adam L; Sharpless, Katherine E; Sjödin, Andreas; Turner, Wayman E; Vander Pol, Stacy S; Wise, Stephen A

    2013-02-01

    Four new Standard Reference Materials (SRMs) have been developed to assist in the quality assurance of chemical contaminant measurements required for human biomonitoring studies, SRM 1953 Organic Contaminants in Non-Fortified Human Milk, SRM 1954 Organic Contaminants in Fortified Human Milk, SRM 1957 Organic Contaminants in Non-Fortified Human Serum, and SRM 1958 Organic Contaminants in Fortified Human Serum. These materials were developed as part of a collaboration between the National Institute of Standards and Technology (NIST) and the Centers for Disease Control and Prevention (CDC) with both agencies contributing data used in the certification of mass fraction values for a wide range of organic contaminants including polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, polybrominated diphenyl ether (PBDE) congeners, and polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners. The certified mass fractions of the organic contaminants in unfortified samples, SRM 1953 and SRM 1957, ranged from 12 ng/kg to 2200 ng/kg with the exception of 4,4'-DDE in SRM 1953 at 7400 ng/kg with expanded uncertainties generally <14 %. This agreement suggests that there were no significant biases existing among the multiple methods used for analysis.

  11. Preparation and application of a fortified hair reference material for the determination of methamphetamine and amphetamine.

    PubMed

    Lee, Sooyeun; Park, Yonghoon; Han, Eunyoung; Choe, Sanggil; Lim, Miae; Chung, Heesun

    2008-07-01

    Quality assurance is one of the major issues in forensic analytical laboratories, where the need for a reference material (RM) has rapidly increased. RMs are very useful for method development and validation, internal quality control or proficiency tests. In the present study, we prepared a RM using drug-free hair for the determination of methamphetamine (MA) and its main metabolite, amphetamine (AP) according to the recommendations of ISO Guide 35. The concentrations of MA and AP were determined using two extraction methods, agitation with 1% HCl in methanol at 38 degrees C and ultrasonication with methanol/5M HCl (20:1), followed by gas chromatography/mass spectrometry (GC/MS) after derivatization with trifluoroacetic anhydride (TFAA). The assignment of values was conducted through the homogeneity study and characterization of the material. Furthermore, an internal proficiency test was performed with the prepared RM, of which the results were compared with those of the authentic hair RM prepared in our previous study. As a result, a hair RM containing MA and AP was prepared at the level of 4.86+/-0.69 ng/mg and 4.63+/-0.44 ng/mg, respectively. Most participants showed satisfactory performances in the internal proficiency test with the both RMs. The hair RM prepared in this study demonstrated its suitability for quality assurance in forensic laboratories.

  12. Characterization of the Defense Waste Processing Facility (DWPF) Environmental Assessment (EA) glass standard reference material

    SciTech Connect

    Jantzen, C.M.; Bibler, N.E.; Beam, D.C.

    1992-09-30

    Liquid high-level nuclear waste at the Savannah River Site (SRS) will be immobilized by vitrification in borosilicate glass. The glass will be produced and poured into stainless steel canisters in the Defense Waste Processing Facility (DWPF). Other waste form producers, such as West Valley Nuclear Services (WVNS) and the Hanford Waste Vitrification Project (HWVP), will also immobilize high-level radioactive waste in borosilicate glass. The canistered waste will be stored temporarily at each facility for eventual permanent disposal in a geologic repository. The Department of Energy has defined a set of requirements for the canistered waste forms, the Waste Acceptance Preliminary Specifications (WAPS). The current Waste Acceptance Preliminary Specification (WAPS) 1.3, the product consistency specification, requires the waste form producers to demonstrate control of the consistency of the final waste form using a crushed glass durability test, the Product Consistency Test (PCT). In order to be acceptable, a waste glass must be more durable during PCT analysis than the waste glass identified in the DWPF Envirorunental Assessment (EA). In order to supply all the waste form producers with the same standard benchmark glass, 1000 pounds of the EA glass was fabricated. The chemical analyses and characterization of the benchmark EA glass are reported. This material is now available to act as a durability, analytic, and/or redox Standard Reference Material (SRM) for all waste form producers.

  13. Development of a candidate certified reference material of cypermethrin in green tea.

    PubMed

    Sin, Della W M; Chan, Pui-kwan; Cheung, Samuel T C; Wong, Yee-Lok; Wong, Siu-kay; Mok, Chuen-shing; Wong, Yiu-chung

    2012-04-01

    This paper presents the preparation of a candidate certified reference material (CRM) of cypermethrin in green tea, GLHK-11-01a according to the requirements of ISO Guide 34 and 35. Certification of the material was performed using a newly developed isotope dilution mass spectrometry (IDMS) approach, with gas chromatography high resolution mass spectrometry (GC-HRMS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). Statistical analysis (one-way ANOVA) showed excellent agreement of the analytical data sets generated from the two mass spectrometric detections. The characterization methods have also been satisfactorily applied in an Asia-Pacific Metrology Program (APMP) interlaboratory comparison study. Both the GC-HRIDMS and GC-IDMS/MS methods proved to be sufficiently reliable and accurate for certification purpose. The certified value of cypermethrin in dry mass fraction was 148 μg kg(-1) and the associated expanded uncertainty was 14μg kg(-1). The uncertainty budget was evaluated from sample in homogeneity, long-term and short-term stability and variability in the characterization procedure. GLHK-11-01a is primarily developed to support the local and wider testing community on need basis in quality assurance work and in seeking accreditation. PMID:22405308

  14. Development of the NIST bone ash standard reference material for environmental radioactivity measurement.

    PubMed

    Lin, Z; Inn, K G; Altzitzoglou, T; Arnold, D; Cavadore, D; Ham, G J; Korun, M; Wershofen, H; Takata, Y; Young, A

    1998-01-01

    The bone ash standard reference material (SRM), a blend of 4% contaminated human bone and 96% diluent bovine bone, has been developed for radiochemical method validation and quality control for radio-bone analysis. The massic activities of 90Sr, 226Ra, 230Th, 232Th, 234U, 235U, 238U, 238Pu, (239 + 240)Pu and (243 + 244)Cm were certified using a variety of radiochemical procedures and detection methods. Measurements confirmed undetectable radionuclide heterogeneity down to a sample size of 5 g. thereby implying adequate blending of particulate materials with dilution factors of up to 17,900. The results among most of the intercomparison laboratories and their methods were consistent. Disequilibrium was observed for decay chains: 234U(0.67 mBq/g)-230Th(0.47 mBq/g)-226Ra(15.1 mBq/g)-210Pb(23 mBq/g)-210Po(13 mBq/g) and 232Th(0.99 mBq/g)-228 Ra(6.1 mBq/g)-228Th(7.1 mBq/g). The disequilibria were the results of mixing occupationally contaminated human bone with natural bovine bone and the fractionation during internal biological processes. The massic activity of 210Pb, 228Th and 241Am were not certified because of insufficient 228Ra and 241Pu data and lack of knowledge in how 222Rn and its daughters will be fractionated in the SRM bottle over time.

  15. Certification of a reference material of metal content in atmospheric particles deposited on filters.

    PubMed

    Oster, Caroline; Labarraque, Guillaume; Fisicaro, Paola

    2015-04-01

    Air quality is one of the areas in Europe where a series of EU Directives have been published with the aim of achieving improved long-term and harmonised air quality objectives across the European Union. This paper describes the production of a certified reference material, aiming to support QA/QC programmes of analytical laboratories in the framework of the air quality monitoring activities. The certified values are the As, Cd, Ni and Pb masses in PM10 particles deposited on quartz filters (CRM SL-MR-2-PSF-01). All the steps of the certification, i.e. the material characterisation, homogeneity and stability evaluation and uncertainty calculation, were performed according to the ISO guide 35 guidelines. The certification was conducted using the characterisation by a single method approach based on isotope dilution for cadmium, nickel, and lead and gravimetric standard addition calibration for arsenic associated with inductively coupled mass spectrometry (ICP-MS). The amounts of the four elements are in the range of the target values regulated by EU Directives.

  16. Applications of New Synthetic Uranium Reference Materials for Geochemistry Research (Invited)

    NASA Astrophysics Data System (ADS)

    Richter, S.; Weyer, S.; Alonso, A.; Aregbe, Y.; Kuehn, H.; Eykens, R.; Verbruggen, A.; Wellum, R.

    2009-12-01

    For many applications in geochemistry research isotope ratio measurements play a significant role. In geochronology isotope abundances of uranium and its daughter products thorium and lead are being used to determine the age and history of various samples of geological interest. For measuring the isotopic compositions of these elements by mass spectrometry, suitable isotope reference materials are needed to validate measurement procedures and to calibrate multi-collector and ion counting detector systems. IRMM is a recognized provider for nuclear isotope reference materials to the nuclear industry and nuclear safeguards authorities, which are also being applied widely for geochemical applications. The preparation of several new synthetic uranium reference materials at IRMM during the recent five years has provided significant impacts on geochemical research. As an example, the IRMM-074 series of gravimetrically prepared uranium mixtures for linearity testing of secondary electron multipliers (SEMs) has been applied for the redetermination of the secular equilibrium 234U/238U value and the 234U half-life by Cheng et al (2009). Due to the use of IRMM-074, results with smaller uncertainties were obtained, which are shifted by about 0.04% compared to the commonly used values published earlier by Cheng et al. in 2000. This has a significant impact for U isotope measurements in geochemistry.. As a further example, the new double spike IRMM-3636 with a 233U/236U ratio of 1:1 and an expanded uncertainty as low as 0.016% (coverage factor k=2, 95% confidence level) was prepared gravimetrically. This double spike allows internal mass fractionation correction for high precision 235U/238U ratio measurements of close to natural samples. Using the new double spike IRMM-3636, the 235U/238U ratios for several commonly used natural U standard materials from NIST/NBL and IRMM, such as e.g. NBS960 (=NBL CRM-112a), NBS950a,b and IRMM-184, have been re-measured with improved precision

  17. Developing qualitative LC-MS methods for characterization of Vaccinium berry Standard Reference Materials.

    PubMed

    Lowenthal, Mark S; Phillips, Melissa M; Rimmer, Catherine A; Rudnick, Paul A; Simón-Manso, Yamil; Stein, Stephen E; Tchekhovskoi, Dmitrii; Phinney, Karen W

    2013-05-01

    Standard Reference Materials (SRMs) offer the scientific community a stable and homogenous source of material that holds countless application possibilities. Traditionally, the National Institute of Standards and Technology (NIST) has provided SRMs with associated quantitative information (certified values) for a select group of targeted analytes as measured in a solution or complex matrix. While the current needs of the SRM community are expanding to include non-quantitative data, NIST is attempting to broaden the scope of how and what information is offered to the SRM community by providing qualitative information about biomaterials, such as chromatographic fingerprints and profiles of untargeted identifications. In this work, metabolomic and proteomic profiling efforts were employed to characterize a suite of six Vaccinium berry SRMs. In the discovery phase, liquid chromatography-tandem mass spectrometry (LC-MS/MS) data was matched to mass spectral libraries; a subsequent validation phase based on multiple-reaction monitoring LC-MS/MS relied on both retention time matching of authentic standards along with fragmentation data for a qualitative overview of the most prominent organic compounds present. Definitive and putative identifications were determined for over 70 metabolites based on reporting guidelines set forth by the Metabolomics Standards Initiative (Metabolomics 3(3):211-221, 2007), and the capability of electrospray ionization mass spectrometry (ESI-MS) to profile untargeted metabolites within a complex matrix using mass spectral matching is demonstrated. Bottom-up proteomic analyses were possible using peptide databases translated from expressed sequence tags (ESTs). Homology searches provided identification of novel Vaccinium proteins based on homology to related genera. Chromatographic fingerprints of these berry materials were acquired for supplemental qualitative information to be provided to users of these SRMs. An unbounded set of qualitative

  18. Pedo-geochemical baseline content levels and soil quality reference values of trace elements in soils from the Mediterranean (Castilla La Mancha, Spain)

    NASA Astrophysics Data System (ADS)

    Ballesta, Raimundo; Bueno, Paz; Rubi, Juan; Giménez, Rosario

    2010-12-01

    To evaluate trace element soil contamination, geochemical baseline contents and reference values need to be established. Pedo-geochemical baseline levels of trace elements in 72 soil samples of 24 soil profiles from the Mediterranean, Castilla La Mancha, are assessed and soil quality reference values are calculated. Reference value contents (in mg kg-1) were: Sc 50.8; V 123.2; Cr 113.4; Co 20.8; Ni 42.6; Cu 27.0; Zn 86.5; Ga 26.7; Ge 1.3; As 16.7; Se 1.4; Br 20.1; Rb 234.7; Sr 1868.4; Y 38.3; Zr 413.1; Nb 18.7; Mo 2.0; Ag 7.8; Cd 4.4; Sn 8.7; Sb 5.7; I 25.4; Cs 14.2; Ba 1049.3; La 348.4; Ce 97.9; Nd 40.1; Sm 10.7; Yb 4.2; Hf 10.0; Ta 4.0; W 5.5; Tl 2.3; Pb 44.2; Bi 2.2; Th 21.6; U 10.3. The contents obtained for some elements are below or close to the detection limit: Co, Ge, Se, Mo, Ag, Cd, Sb, Yb, Hf, Ta, W, Tl and Bi. The element content ranges (the maximum value minus the minimum value) are: Sc 55.0, V 196.0, Cr 346.0, Co 64.4, Ni 188.7, Cu 49.5, Zn 102.3, Ga 28.7, Ge 1.5, As 26.4, Se 0.9, Br 33.0 Rb 432.7, Sr 3372.6, Y 39.8, Zr 523.2, Nb 59.7, Mo 3.9, Ag 10.1, Cd 1.8, Sn 75.2, Sb 9.9, I 68.0, Cs 17.6, Ba 1394.9, La 51.3, Ce 93.5, Nd 52.5, Sm 11.2, Yb 4.2, Hf 11.3, Ta 6.3, W 5.2, Tl 2.1, Pb 96.4, Bi 3.0, Th 24.4, U 16.4 (in mg kg-1). The spatial distribution of the elements was affected mainly by the nature of the bedrock and by pedological processes. The upper limit of expected background variation for each trace element in the soil is documented, as is its range as a criterion for evaluating which sites may require decontamination.

  19. Applications of New Synthetic Uranium Reference Materials for Research in Geochemistry

    NASA Astrophysics Data System (ADS)

    Richter, Stephan; Alonso, Adolfo; Aregbe, Yetunde; Eykens, Roger; Jacobsson, Ulf; Kuehn, Heinz; Verbruggen, Andre; Weyer, Stefan

    2010-05-01

    For many applications in geochemistry research isotope ratio measurements play a significant role. In geochronology isotope abundances of uranium and its daughter products thorium and lead are being used to determine the age and history of various samples of geological interest. For measuring the isotopic compositions of these elements by mass spectrometry, suitable isotope reference materials are needed to validate measurement procedures and to calibrate multi-collector and ion counting detector systems. IRMM is a recognized provider for nuclear isotope reference materials to the nuclear industry and nuclear safeguards authorities, which are also being applied widely for geochemical applications. Firstly, the double spike IRMM-3636 with a 233U/236U ratio of 1:1 was prepared which allows internal mass fractionation correction for high precision 235U/238U ratio measurements. The 234U abundance of this double spike material is low enough to allow an accurate and precise correction of 234U/238U ratios, even for measurements of close to equilibrium uranium samples. The double spike IRMM-3636 is offered in 3 concentrations: 1mg/g, 0.1mg/g and 0.005mg/g. Secondly, the 236U single spike IRMM-3660 was prepared and is offered in 3 concentrations: 1mg/g, 0.1mg/g and 0.01mg/g. Thirdly, a "Quad"-isotope reference material, IRMM-3101, has been prepared which is characterized by 233U/235U/236U/238U=1/1/1/1. This material is useful for checking Faraday cup efficiencies and inter-calibration of MIC (multiple ion counting) detectors. The quad-IRM is offered in 3 concentrations: 1mg/g, 0.1mg/g and 0.01mg/g. As one example for the significant influence of synthetic reference materials for geochemical research, the IRMM-074 series of gravimetrically prepared uranium mixtures for linearity testing of secondary electron multipliers (SEMs) has been applied for the redetermination of the secular equilibrium 234U/238U value and the 234U half-life by Cheng et al (2009). Due to the use of

  20. New Organic Stable Isotope Reference Materials for Distribution through the USGS and the IAEA

    NASA Astrophysics Data System (ADS)

    Schimmelmann, Arndt; Qi, Haiping

    2014-05-01

    The widespread adoption of relative stable isotope-ratio measurements in organic matter by diverse scientific disciplines is at odds with the dearth of international organic stable isotopic reference materials (RMs). Only two of the few carbon (C) and nitrogen (N) organic RMs, namely L-glutamic acids USGS40 and USGS41 [1], both available from the U.S. Geological Survey (USGS) and the International Atomic Energy Agency (IAEA), provide an isotopically contrasting pair of organic RMs to enable essential 2-point calibrations for δ-scale normalization [2, 3]. The supply of hydrogen (H) organic RMs is even more limited. Numerous stable isotope laboratories have resorted to questionable practices, for example by using 'CO2, N2, and H2 reference gas pulses' for isotopic calibrations, which violates the principle of identical treatment of sample and standard (i.e., organic unknowns should be calibrated directly against chemically similar organic RMs) [4], or by using only 1 anchor instead of 2 for scale calibration. The absence of international organic RMs frequently serves as an excuse for indefensible calibrations. In 2011, the U.S. National Science Foundation (NSF) funded an initiative of 10 laboratories from 7 countries to jointly develop much needed new organic RMs for future distribution by the USGS and the IAEA. The selection of targeted RMs attempts to cover various common compound classes of broad technical and scientific interest. We had to accept compromises to approach the ideal of high chemical stability, lack of toxicity, and low price of raw materials. Hazardous gases and flammable liquids were avoided in order to facilitate international shipping of future RMs. With the exception of polyethylene and vacuum pump oil, all organic RMs are individual, chemically-pure substances, which can be used for compound-specific isotopic measurements in conjunction with liquid and gas chromatographic interfaces. The compounds listed below are under isotopic calibration by

  1. Hygrothermal Material Properties for Soils in Building Science

    SciTech Connect

    Kehrer, Manfred; Pallin, Simon B

    2013-01-01

    Saving energy in buildings is top of mind with today s building professionals. Although designing energy-efficient walls and roofs is mostly a no-brainer, ensuring that below-grade foundations do not generate moisture problems has become even more complex, particularly because of how soil is involved. Hygrothermal performance of soils coupled to buildings is complicated because of the dearth of information on soil properties. A computational approach for heat transfer through the ground has been well-defined, and simplified methods have been developed. These approaches, however, generally ignore the transfer of soil moisture, which is not negligible. The intention of an ongoing study at Oak Ridge (TN) National Laboratory, therefore, is to gather, comprehend and adapt soil properties from soil science as well. The obtained information must be applicable to related tasks in building science and validated with hygrothermal calculation tools, where additional plugins to the existing software code WUFI (an acronym for Warme unde Felichte Instructionar, which translates to unsteady heat and moisture) are required. (See the sidebar, opposite page, for specifics on WUFI.)Simulation results from WUFI are being compared with existing thermal-only measurements and are being accomplished with ongoing hygrothermal measurements. The final outcome of the study will be the evaluation of several soil types in several climate zones for a number of basement assembly types. The study will define the type of soil, together with the type of building construction considered most and least reliable with respect to energy consumption and moisture safety. Furthermore, the study will determine the influences that different soils have on total energy loss through the ground.

  2. Reference levels of background radioactivity for beach sands and soils in İnebolu/Kastamonu-Turkey

    NASA Astrophysics Data System (ADS)

    Kurnaz, Aslı; Türkdoǧan, Savaş; Hançerlioǧulları, Aybaba; ćetiner, M. Atıf

    2016-03-01

    This paper presents the measurement results of environmental radioactivity levels for İnebolu district (tourist area), Kastamonu-Turkey. The radioactivity concentrations of 238U, 232Th, 40K and the fission product 137Cs in soil samples collected from 13 region surroundings of study area and in 12 beach sand samples collected from along the coast of İnebolu were determined. To evaluate the radiological hazard of the natural radioactivity, based on the measured concentrations of these radionuclides, the mean absorbed gamma dose and the annual effective dose were evaluated separately, and found to be 112.90 nGy h-1 and 138.46 µSv y-1 for soil samples and 75.19 nGy h-1 and 92.22 µSv y-1 for beach sand samples, respectively. The results show that İnebolu does not have high background.

  3. Plant material as bioaccumulator of arsenic in soils affected by mining activities

    NASA Astrophysics Data System (ADS)

    Martínez-López, Salvadora; Martínez-Sánchez, Maria Jose; García-Lorenzo, Maria Luz; Pérez-Sirvent, Carmen

    2010-05-01

    Heavy metal contamination is an important environmental problem, since the metals are harmful to humans, animals and tend to bioaccumulate in the food chain. The aim of this study was to determine the total concentration of As, As (III) and As(V) in soil samples, leaves and roots of plant material, growing in a mining area in Spain (Murcia). Ditichia viscosa was used as the plant of reference. The concentrations of bioavailable As in plant samples were calculated by different soil chemical extraction methods; deionized water, 0.5N NaHCO3 (Olsen extraction), oxidizable medium, 0.5 HCl, 0.05M (NH4)2SO4, 0.005M DTPA and Mehra-Jackson extraction. For this study, fourteen samples were collected in the surrounding area of Sierra Minera and Portman Bay (Murcia, SE Spain). Samples were air dried and sieved to < 2mm for general analytical determinations. To determine the As content, soil samples were first ground to a fine powder using an agate ball mill. Fresh vegetable samples were separated into root and aboveground biomass and then lyophilized. Arsenic levels were obtained by using atomic fluorescence spectrometry with an automated continuous flow hydride generation (HG-AFS) spectrometer. Samples showed pH average values close to neutrality. Most samples showed a very low organic matter percentage. Electrical conductivity and calcium carbonate content were considerably low in most samples. The mineralogical analysis showed that the main minerals were quartz, muscovite, kaolinite and illite, while the minority minerals were alteration products derived of mining activities (iron oxides and hydroxides, siderite, jarosite and gypsum), calcite and feldspars. Although the plants do not absorb arsenic in the same proportion, the results suggest that a good relationship exists between the total content of As in soil and the total content in plant. The results showed that the arsenic content in roots was positively correlated with the oxidizable-organic matter and sulfides

  4. Growth of barley exposed to solvent refined coal (SRC) materials added to soil

    SciTech Connect

    Cline, J.F.; Rickard, W.H.; Thiede, M.E.

    1980-01-01

    The growth of barley plants (Hordeum vulgare) grown in Ritzville silt loam soil, treated with solvent refined coal material, SRC solid (SRC I) and SRC liquid (SRC II) was examined. Although the SRC materials will not be introduced to soil or surface waters in normal uses, they could be spilled during transportation. Such spills could contaminate surface waters and agricultural, rangeland and forest soils, possibly causing acute or chronic damage to plants and also provide a way for certain inorganic and organic materials to enter food chains.

  5. Development of a reference material of a single DNA molecule for the quality control of PCR testing.

    PubMed

    Mano, Junichi; Hatano, Shuko; Futo, Satoshi; Yoshii, Junji; Nakae, Hiroki; Naito, Shigehiro; Takabatake, Reona; Kitta, Kazumi

    2014-09-01

    We developed a reference material of a single DNA molecule with a specific nucleotide sequence. The double-strand linear DNA which has PCR target sequences at the both ends was prepared as a reference DNA molecule, and we named the PCR targets on each side as confirmation sequence and standard sequence. The highly diluted solution of the reference molecule was dispensed into 96 wells of a plastic PCR plate to make the average number of molecules in a well below one. Subsequently, the presence or absence of the reference molecule in each well was checked by real-time PCR targeting for the confirmation sequence. After an enzymatic treatment of the reaction mixture in the positive wells for the digestion of PCR products, the resultant solution was used as the reference material of a single DNA molecule with the standard sequence. PCR analyses revealed that the prepared samples included only one reference molecule with high probability. The single-molecule reference material developed in this study will be useful for the absolute evaluation of a detection limit of PCR-based testing methods, the quality control of PCR analyses, performance evaluations of PCR reagents and instruments, and the preparation of an accurate calibration curve for real-time PCR quantitation.

  6. Development of a reference material of a single DNA molecule for the quality control of PCR testing.

    PubMed

    Mano, Junichi; Hatano, Shuko; Futo, Satoshi; Yoshii, Junji; Nakae, Hiroki; Naito, Shigehiro; Takabatake, Reona; Kitta, Kazumi

    2014-09-01

    We developed a reference material of a single DNA molecule with a specific nucleotide sequence. The double-strand linear DNA which has PCR target sequences at the both ends was prepared as a reference DNA molecule, and we named the PCR targets on each side as confirmation sequence and standard sequence. The highly diluted solution of the reference molecule was dispensed into 96 wells of a plastic PCR plate to make the average number of molecules in a well below one. Subsequently, the presence or absence of the reference molecule in each well was checked by real-time PCR targeting for the confirmation sequence. After an enzymatic treatment of the reaction mixture in the positive wells for the digestion of PCR products, the resultant solution was used as the reference material of a single DNA molecule with the standard sequence. PCR analyses revealed that the prepared samples included only one reference molecule with high probability. The single-molecule reference material developed in this study will be useful for the absolute evaluation of a detection limit of PCR-based testing methods, the quality control of PCR analyses, performance evaluations of PCR reagents and instruments, and the preparation of an accurate calibration curve for real-time PCR quantitation. PMID:25061686

  7. Retrospective Analysis of NIST Standard Reference Material 1450, Fibrous Glass Board, for Thermal Insulation Measurements.

    PubMed

    Zarr, Robert R; Heckert, N Alan; Leigh, Stefan D

    2014-01-01

    Thermal conductivity data acquired previously for the establishment of Standard Reference Material (SRM) 1450, Fibrous Glass Board, as well as subsequent renewals 1450a, 1450b, 1450c, and 1450d, are re-analyzed collectively and as individual data sets. Additional data sets for proto-1450 material lots are also included in the analysis. The data cover 36 years of activity by the National Institute of Standards and Technology (NIST) in developing and providing thermal insulation SRMs, specifically high-density molded fibrous-glass board, to the public. Collectively, the data sets cover two nominal thicknesses of 13 mm and 25 mm, bulk densities from 60 kg·m(-3) to 180 kg·m(-3), and mean temperatures from 100 K to 340 K. The analysis repetitively fits six models to the individual data sets. The most general form of the nested set of multilinear models used is given in the following equation: [Formula: see text]where λ(ρ,T) is the predicted thermal conductivity (W·m(-1)·K(-1)), ρ is the bulk density (kg·m(-3)), T is the mean temperature (K) and ai (for i = 1, 2, … 6) are the regression coefficients. The least squares fit results for each model across all data sets are analyzed using both graphical and analytic techniques. The prevailing generic model for the majority of data sets is the bilinear model in ρ and T. [Formula: see text] One data set supports the inclusion of a cubic temperature term and two data sets with low-temperature data support the inclusion of an exponential term in T to improve the model predictions. Physical interpretations of the model function terms are described. Recommendations for future renewals of SRM 1450 are provided. An Addendum provides historical background on the origin of this SRM and the influence of the SRM on external measurement programs.

  8. Earth's earliest biosphere-a proposal to develop a collection of curated archean geologic reference materials.

    PubMed

    Lindsay, John F; McKay, David S; Allen, Carlton C

    2003-01-01

    The discovery of evidence indicative of life in a Martian meteorite has led to an increase in interest in astrobiology. As a result of this discovery, and the ensuing controversy, it has become apparent that our knowledge of the early development of life on Earth is limited. Archean stratigraphic successions containing evidence of Earth's early biosphere are well preserved in the Pilbara Craton of Western Australia. The craton includes part of a protocontinent consisting of granitoid complexes that were emplaced into, and overlain by, a 3.51-2.94 Ga volcanigenic carapace - the Pilbara Supergroup. The craton is overlain by younger supracrustal basins that form a time series recording Earth history from approximately 2.8 Ga to approximately 1.9 Ga. It is proposed that a well-documented suite of these ancient rocks be collected as reference material for Archean and astrobiological research. All samples would be collected in a well-defined geological context in order to build a framework to test models for the early evolution of life on Earth and to develop protocols for the search for life on other planets.

  9. Earth's earliest biosphere-a proposal to develop a collection of curated archean geologic reference materials

    NASA Technical Reports Server (NTRS)

    Lindsay, John F.; McKay, David S.; Allen, Carlton C.

    2003-01-01

    The discovery of evidence indicative of life in a Martian meteorite has led to an increase in interest in astrobiology. As a result of this discovery, and the ensuing controversy, it has become apparent that our knowledge of the early development of life on Earth is limited. Archean stratigraphic successions containing evidence of Earth's early biosphere are well preserved in the Pilbara Craton of Western Australia. The craton includes part of a protocontinent consisting of granitoid complexes that were emplaced into, and overlain by, a 3.51-2.94 Ga volcanigenic carapace - the Pilbara Supergroup. The craton is overlain by younger supracrustal basins that form a time series recording Earth history from approximately 2.8 Ga to approximately 1.9 Ga. It is proposed that a well-documented suite of these ancient rocks be collected as reference material for Archean and astrobiological research. All samples would be collected in a well-defined geological context in order to build a framework to test models for the early evolution of life on Earth and to develop protocols for the search for life on other planets.

  10. Earth's earliest biosphere-a proposal to develop a collection of curated archean geologic reference materials.

    PubMed

    Lindsay, John F; McKay, David S; Allen, Carlton C

    2003-01-01

    The discovery of evidence indicative of life in a Martian meteorite has led to an increase in interest in astrobiology. As a result of this discovery, and the ensuing controversy, it has become apparent that our knowledge of the early development of life on Earth is limited. Archean stratigraphic successions containing evidence of Earth's early biosphere are well preserved in the Pilbara Craton of Western Australia. The craton includes part of a protocontinent consisting of granitoid complexes that were emplaced into, and overlain by, a 3.51-2.94 Ga volcanigenic carapace - the Pilbara Supergroup. The craton is overlain by younger supracrustal basins that form a time series recording Earth history from approximately 2.8 Ga to approximately 1.9 Ga. It is proposed that a well-documented suite of these ancient rocks be collected as reference material for Archean and astrobiological research. All samples would be collected in a well-defined geological context in order to build a framework to test models for the early evolution of life on Earth and to develop protocols for the search for life on other planets. PMID:14987479

  11. The preparation of uranium-doped glass reference materials for environmental measurements

    NASA Astrophysics Data System (ADS)

    Raptis, K.; Ingelbrecht, C.; Wellum, R.; Alonso, A.; De Bolle, W.; Perrin, R.

    2002-03-01

    Seven different uranium glass powders containing 5 mass% uranium with 235U abundances from natural to highly enriched have been prepared for the IRMM support programme to the International Atomic Energy Agency (IAEA) and for the IRMM external NUSIMEP quality control programme (Nuclear Signatures Interlaboratory Measurement Evaluation Programme). The particles will be primarily used, blended with (inactive) matrix glass powder in various ratios to simulate environmental samples containing "hot" particles in order to assess the performance of various separation and measurement techniques. High-purity borosilicate glass was prepared by blending of powders, melting and grinding by ball milling and jet milling to a powder of about 12 μm. A quantity of this glass was then blended with U 3O 8, melted and milled to powder. Laser diffraction measurements were made to ensure that the particle size distribution of the uranium glass matched that of the matrix glass in order to ensure homogeneous blending. The final yield was 30-40 g of each uranium glass and 1 kg of matrix glass. The glasses have been certified as reference materials for isotope abundances of uranium.

  12. Uranium Isotopic Ratio Measurements of U3O8 Reference Materials by Atom Probe Tomography

    SciTech Connect

    Fahey, Albert J.; Perea, Daniel E.; Bartrand, Jonah AG; Arey, Bruce W.; Thevuthasan, Suntharampillai

    2016-01-01

    We report results of measurements of isotopic ratios obtained with atom probe tomography on U3O8 reference materials certified for their isotopic abundances of uranium. The results show good agreement with the certified values. High backgrounds due to tails from adjacent peaks complicate the measurement of the integrated peak areas as well as the fact that only oxides of uranium appear in the spectrum, the most intense of which is doubly charged. In addition, lack of knowledge of other instrumental parameters, such as the dead time, may bias the results. Isotopic ratio measurements can be performed at the nanometer-scale with the expectation of sensible results. The abundance sensitivity and mass resolving power of the mass spectrometer are not sufficient to compete with magnetic-sector instruments but are not far from measurements made by ToF-SIMS of other isotopic systems. The agreement of the major isotope ratios is more than sufficient to distinguish most anthropogenic compositions from natural.

  13. Application of Uranium Isotope Dilution Mass Spectrometry in the preparation of New Certified Reference Materials

    NASA Astrophysics Data System (ADS)

    Hasözbek, A.; Mathew, K. J.; Orlowicz, G.; Srinivasan, B.; Narayanan, U.

    2012-04-01

    Proven measurement techniques play a critical role in the preparation of Certified Reference Materials (CRMs) - those requiring high accuracy and precision in the measurement results. Isotope Dilution Mass Spectrometry (IDMS) is one such measurement method commonly used in the quantitative analysis of uranium in nuclear safeguards and isotope geology applications. In this project, we evaluated the possibility of using some of the uranium isotopic and assay CRMs made earlier by the New Brunswick laboratory as IDMS spikes to define the uranium mass fraction in future preparations of CRMs. Uranium solutions prepared from CRM 112-A (a highly pure uranium metal assay standard) and CRM 115 (a highly pure uranium oxide isotopic and assay standard) were used as spikes in the determination of uranium. Two different thermal ionization mass spectrometer instruments (MAT 261 and TRITON) were used for the isotopic measurements. Standard IDMS equation was used for data reduction to yield results for uranium mass fraction along with uncertainties, the latter calculated according to GUM. The results show that uranium mass fraction measurements can be made with the required accuracy and precision for defining the uranium concentration in new CRMs as well as in routine samples analyses.

  14. Uranium isotopic ratio measurements of U3O8 reference materials by atom probe tomography.

    PubMed

    Fahey, Albert J; Perea, Daniel E; Bartrand, Jonah; Arey, Bruce W; Thevuthasan, Suntharampillai

    2016-03-01

    We report results of measurements of isotopic ratios obtained with atom probe tomography on U3O8 reference materials certified for their isotopic abundances of uranium. The results show good agreement with the certified values. High backgrounds due to tails from adjacent peaks complicate the measurement of the integrated peak areas as well as the fact that only oxides of uranium appear in the spectrum, the most intense of which is doubly charged. In addition, lack of knowledge of other instrumental parameters, such as the dead time, may bias the results. Isotopic ratio measurements can be performed at the nanometer-scale with the expectation of sensible results. The abundance sensitivity and mass resolving power of the mass spectrometer are not sufficient to compete with magnetic-sector instruments but are not far from measurements made by ToF-SIMS of other isotopic systems. The agreement of the major isotope ratios is more than sufficient to distinguish most anthropogenic compositions from natural. PMID:26774651

  15. Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 1: Calibration Solutions.

    PubMed

    Beach, Daniel G; Crain, Sheila; Lewis, Nancy; LeBlanc, Patricia; Hardstaff, William R; Perez, Ruth A; Giddings, Sabrina D; Martinez-Farina, Camilo F; Stefanova, Roumiana; Burton, Ian W; Kilcoyne, Jane; Melanson, Jeremy E; Quilliam, Michael A; McCarron, Pearse

    2016-09-01

    Okadaic acid (OA) and its analogs dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic polyethers produced by marine dinoflagellates. These toxins accumulate in shellfish and cause diarrhetic shellfish poisoning (DSP) in humans. Regulatory testing of shellfish is essential to safeguard public health and for international trade. Certified reference materials (CRMs) play a key role in analytical monitoring programs. This paper presents an overview of the interdisciplinary work that went into the planning, production, and certification of calibration-solution CRMs for OA, DTX1, and DTX2. OA and DTX1 were isolated from large-scale algal cultures and DTX2 from naturally contaminated mussels. Toxins were isolated by a combination of extraction and chromatographic steps with processes adapted to suit the source and concentration of each toxin. New 19-epi-DSP toxin analogs were identified as minor impurities. Once OA, DTX1, and DTX2 were established to be of suitable purity, solutions were prepared and dispensed into flame-sealed glass ampoules. Certification measurements were carried out using quantitative NMR spectroscopy and LC-tandem MS. Traceability of measurements was established through certified external standards of established purity. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization, with components from the measurement, stability, and homogeneity studies being propagated into final combined uncertainties. PMID:27524810

  16. Neutron-activation analysis of several US Geological Survey and National Bureau of Standards reference materials

    SciTech Connect

    Daly, A.T.

    1981-01-01

    In this work, several US Geological Survey (U.S.G.S.) and National Bureau of Standards (N.B.S.) reference samples have been analyzed in an effort to improve the quality of elemental concentration data available on these materials, so they can be used in a program of verification of factor analysis source resolution procedures. The analyses of these samples were performed by instrumental neutron activation analysis (INAA). The samples analyzed were: U.S.G.S. Green River Shale, N.B.S. 45b Homogeneous River Sediment, U.S.G.S. Analyzed Peridotite N.B.S. 1579 Powdered Lead-based Paint, U.S.G.S. Hawaian Basalt U.S.G.S. Marine Mud, U.S.G.S. Analyzed Cody Shale U.S.G.S. Glass Mountain Rhyolite, N.B.S. Argillaceous Limestone No. 1, and a sample of Spex ultrapure graphite. Neutron activation analysis was employed because of the high sensitivity that can be attained in determining elemental concentrations. Although INAA is a relatively simple method and the reproducibility of the data is good, the method shows some inaccuracies. The basic theory and technique are reviewed in an attempt to show where problems can arise and how they can be dealt with.

  17. Determination of multielements in a typical Japanese diet certified reference material by instrumental neutron activation analysis.

    PubMed

    Suzuki, Shogo; Okada, Yukiko; Hirai, Shoji

    2003-08-01

    Multielements in a typical Japanese diet certified reference material prepared at the National Institute for Environmental Studies (NIES) of Japan, in collaboration with the National Institute of Radiological Sciences (NIRS) of Japan were determined by instrumental neutron activation analysis (INAA). Five samples (ca. 510-1000 mg) and comparative standards were irradiated for a short time (10 s) at a thermal neutron flux of 1.5 x 10(12) n cm(-2) s(-1) (pneumatic transfer) and for a long time (6 h) at a thermal neutron flux of 3.7 x 10(12) n cm(-2) s(-1) (central thimble) in the Rikkyo University Research Reactor (TRIGA Mark-II, 100 kW). The irradiated samples were measured by conventional gama-ray spectrometry using a coaxial Ge detector, and by anti-coincidence and coincidence gamma-ray spectrometry with a coaxial Ge detector and a well-type NaI(Tl) detector. The concentrations of 38 elements were determined by these methods. PMID:12945682

  18. Reduction and persulfate oxidation of nitro explosives in contaminated soils using Fe-bearing materials.

    PubMed

    Oh, Seok-Young; Yoon, Hyun-Su; Jeong, Tae-Yong; Kim, Sang Don; Kim, Dong-Wook

    2016-07-13

    The oxidative and reductive transformation of nitro explosives in contaminated soils with Fe-bearing materials and persulfate (S2O8(2-)) was examined via batch experiments. Zero-valent cast iron [Fe(0)], steel dust from a steel manufacturing plant, and FeS rapidly reduced 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in soil under anaerobic conditions as long as a sufficient amount of water was present. The Fe-bearing materials also effectively activated persulfate to enhance the oxidative transformation of TNT and RDX in soil-water systems. Kinetically, reductive and oxidative transformations removed more than 90% of the explosives from a soil-water system within 5 h under the given conditions. Pseudo-first-order rates in the range of 0.7-23.4 h(-1) were observed. By increasing the concentration of persulfate or Fe-bearing materials, the oxidative transformation could be promoted. Treated soils via redox reactions using the Fe-bearing materials did not show significant toxicity, except for the case of TNT-contaminated soils oxidized by FeS-assisted persulfate. Considering the kinetics of explosive degradation and the toxicity of treated wastewaters and soils, Fe(0) or steel dust-assisted persulfate oxidation may be a safe option as an ex situ remediation process for the treatment of explosive-contaminated soils.

  19. Military Curriculum Materials for Vocational and Technical Education. Soils Engineering 3-1. Edition 1.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This individualized, self-paced course for independent study in soils engineering was adapted from military curriculum materials for use in vocational education. The course is designed to acquaint students with various soil types and their characteristics using various procedures, tests, and recording forms. Some of these duties are determining…

  20. Unit The World of the Soil, First Trial Materials, Inspection Set, [Australian Science Education Project].

    ERIC Educational Resources Information Center

    Australian Council for Educational Research, Hawthorn.

    The Australian Science Education project is producing materials designed for use in grades 7 - 10 of Australian schools. This is the first trial version of a unit expected to take about 20 40-minute periods to complete. Included are a teacher's guide to the unit, four pupil booklets ("Looking at Soils,""Things to do With Soils,""What is it…

  1. Reduction and persulfate oxidation of nitro explosives in contaminated soils using Fe-bearing materials.

    PubMed

    Oh, Seok-Young; Yoon, Hyun-Su; Jeong, Tae-Yong; Kim, Sang Don; Kim, Dong-Wook

    2016-07-13

    The oxidative and reductive transformation of nitro explosives in contaminated soils with Fe-bearing materials and persulfate (S2O8(2-)) was examined via batch experiments. Zero-valent cast iron [Fe(0)], steel dust from a steel manufacturing plant, and FeS rapidly reduced 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in soil under anaerobic conditions as long as a sufficient amount of water was present. The Fe-bearing materials also effectively activated persulfate to enhance the oxidative transformation of TNT and RDX in soil-water systems. Kinetically, reductive and oxidative transformations removed more than 90% of the explosives from a soil-water system within 5 h under the given conditions. Pseudo-first-order rates in the range of 0.7-23.4 h(-1) were observed. By increasing the concentration of persulfate or Fe-bearing materials, the oxidative transformation could be promoted. Treated soils via redox reactions using the Fe-bearing materials did not show significant toxicity, except for the case of TNT-contaminated soils oxidized by FeS-assisted persulfate. Considering the kinetics of explosive degradation and the toxicity of treated wastewaters and soils, Fe(0) or steel dust-assisted persulfate oxidation may be a safe option as an ex situ remediation process for the treatment of explosive-contaminated soils. PMID:27327861

  2. Bioremediation of soils, sludges, and materials contaminated with toxic metals or radionuclides

    SciTech Connect

    Francis, A.J.

    1993-04-01

    Bioremediation stabilizes and reclaims radionuclide or toxic metal-contaminated materials, soils, sediments, or wastes; it then recovers the contaminating radionuclides and metals. Waste materials are stabilized and reduced in volume using anaerobic bacteria; or alternatively, materials are treated with citric acid before bioremediation begins. Photolysis is used after bioremediation to release radionuclides.

  3. Development of Lentivirus-Based Reference Materials for Ebola Virus Nucleic Acid Amplification Technology-Based Assays.

    PubMed

    Mattiuzzo, Giada; Ashall, James; Doris, Kathryn S; MacLellan-Gibson, Kirsty; Nicolson, Carolyn; Wilkinson, Dianna E; Harvey, Ruth; Almond, Neil; Anderson, Robert; Efstathiou, Stacey; Minor, Philip D; Page, Mark

    2015-01-01

    The 2013-present Ebola virus outbreak in Western Africa has prompted the production of many diagnostic assays, mostly based on nucleic acid amplification technologies (NAT). The calibration and performance assessment of established assays and those under evaluation requires reference materials that can be used in parallel with the clinical sample to standardise or control for every step of the procedure, from extraction to the final qualitative/quantitative result. We have developed safe and stable Ebola virus RNA reference materials by encapsidating anti sense viral RNA into HIV-1-like particles. The lentiviral particles are replication-deficient and non-infectious due to the lack of HIV-1 genes and Envelope protein. Ebola virus genes were subcloned for encapsidation into two lentiviral preparations, one containing NP-VP35-GP and the other VP40 and L RNA. Each reference material was formulated as a high-titre standard for use as a calibrator for secondary or internal standards, and a 10,000-fold lower titre preparation to serve as an in-run control. The preparations have been freeze-dried to maximise stability. These HIV-Ebola virus RNA reference materials were suitable for use with in-house and commercial quantitative RT-PCR assays and with digital RT-PCR. The HIV-Ebola virus RNA reference materials are stable at up to 37°C for two weeks, allowing the shipment of the material worldwide at ambient temperature. These results support further evaluation of the HIV-Ebola virus RNA reference materials as part of an International collaborative study for the establishment of the 1st International Standard for Ebola virus RNA.

  4. Development of Lentivirus-Based Reference Materials for Ebola Virus Nucleic Acid Amplification Technology-Based Assays

    PubMed Central

    Mattiuzzo, Giada; Ashall, James; Doris, Kathryn S.; MacLellan-Gibson, Kirsty; Nicolson, Carolyn; Wilkinson, Dianna E.; Harvey, Ruth; Almond, Neil; Anderson, Robert; Efstathiou, Stacey; Minor, Philip D.; Page, Mark

    2015-01-01

    The 2013-present Ebola virus outbreak in Western Africa has prompted the production of many diagnostic assays, mostly based on nucleic acid amplification technologies (NAT). The calibration and performance assessment of established assays and those under evaluation requires reference materials that can be used in parallel with the clinical sample to standardise or control for every step of the procedure, from extraction to the final qualitative/quantitative result. We have developed safe and stable Ebola virus RNA reference materials by encapsidating anti sense viral RNA into HIV-1-like particles. The lentiviral particles are replication-deficient and non-infectious due to the lack of HIV-1 genes and Envelope protein. Ebola virus genes were subcloned for encapsidation into two lentiviral preparations, one containing NP-VP35-GP and the other VP40 and L RNA. Each reference material was formulated as a high-titre standard for use as a calibrator for secondary or internal standards, and a 10,000-fold lower titre preparation to serve as an in-run control. The preparations have been freeze-dried to maximise stability. These HIV-Ebola virus RNA reference materials were suitable for use with in-house and commercial quantitative RT-PCR assays and with digital RT-PCR. The HIV-Ebola virus RNA reference materials are stable at up to 37°C for two weeks, allowing the shipment of the material worldwide at ambient temperature. These results support further evaluation of the HIV-Ebola virus RNA reference materials as part of an International collaborative study for the establishment of the 1st International Standard for Ebola virus RNA. PMID:26562415

  5. Data Collection Handbook to Support Modeling Impacts of Radioactive Material in Soil and Building Structures

    SciTech Connect

    Yu, Charley; Kamboj, Sunita; Wang, Cheng; Cheng, Jing-Jy

    2015-09-01

    This handbook is an update of the 1993 version of the Data Collection Handbook and the Radionuclide Transfer Factors Report to support modeling the impact of radioactive material in soil. Many new parameters have been added to the RESRAD Family of Codes, and new measurement methodologies are available. A detailed review of available parameter databases was conducted in preparation of this new handbook. This handbook is a companion document to the user manuals when using the RESRAD (onsite) and RESRAD-OFFSITE code. It can also be used for RESRAD-BUILD code because some of the building-related parameters are included in this handbook. The RESRAD (onsite) has been developed for implementing U.S. Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), crops and livestock, human intake, source characteristic, and building characteristic parameters are used in the RESRAD (onsite) code. The RESRAD-OFFSITE code is an extension of the RESRAD (onsite) code and can also model the transport of radionuclides to locations outside the footprint of the primary contamination. This handbook discusses parameter definitions, typical ranges, variations, and measurement methodologies. It also provides references for sources of additional information. Although this handbook was developed primarily to support the application of RESRAD Family of Codes, the discussions and values are valid for use of other pathway analysis models and codes.

  6. Detection of tritium sorption on four soil materials.

    PubMed

    Teng, Yanguo; Zuo, Rui; Wang, Jinsheng; Hu, Qinhong; Sun, Zongjian; Zeng, Ni

    2011-02-01

    In order to measure groundwater age and design nuclear waste disposal sites, it is important to understand the sorption behavior of tritium on soils. In this study, batch tests were carried out using four soils from China: silty clays from An County and Jiangyou County in Sichuan Province, both of which could be considered candidate sites for Very Low Level Waste disposal; silty sand from Beijing; and loess from Yuci County in Shanxi Province, a typical Chinese loess region. The experimental results indicated that in these soil media, the distribution coefficient of tritium is slightly influenced by adsorption time, water/solid ratio, initial tritium specific activity, pH, and the content of humic and fulvic acids. The average distribution coefficient from all of these influencing factors was about 0.1-0.2 mL/g for the four types of soil samples. This relatively modest sorption of tritium in soils needs to be considered in fate and transport studies of tritium in the environment.

  7. Soil deepening by trees and the effects of parent material

    NASA Astrophysics Data System (ADS)

    Shouse, Michael; Phillips, Jonathan

    2016-09-01

    In some cases biomechanical effects of individual trees may locally deepen or thicken regolith, especially in relatively shallow soils. This biogeomorphic ecosystem engineering phenomenon is at least partly contingent on the geological setting. The purpose of this research was to gain further insight into the biogeomorphic phenomenon, and to assess the relative importance of biomechanical and geological effects. Earlier studies in the Ouachita Mountains of Arkansas showed that individual trees locally thicken the regolith via mechanisms associated with root penetration of bedrock. However, that work was conducted mainly in areas of strongly dipping and contorted rock, where joints and bedding planes susceptible to root penetration were thought to be common and accessible. This project extended the research to the Cumberland Plateau region of Kentucky, where flat, level-bedded sedimentary rocks are dominant. Soil depth beneath trees was compared to that of non-tree sites by measuring depth to bedrock beneath rotted tree stumps and at adjacent sites with 1.0 m. While soil thickness beneath stumps was greater in the Ouachita Mountains compared to the Kentucky sites, in both regions soils beneath stumps are significantly deeper than adjacent soils. Further, there were no statistically significant differences in the difference between stump and adjacent sites between the two regions. This suggests the local deepening effects of trees occur in flat-bedded as well as steeply dipping lithologies.

  8. Trace elements in soil and biota in confined disposal facilities for dredged material.

    PubMed

    Beyer, W N; Miller, G; Simmers, J W

    1990-01-01

    We studied the relation of trace element concentrations in soil to those in house mice (Mus musculus), common reed (Phragmites australis) and ladybugs (Coccinella septempunctata at five disposal facilities for dredged material. The sites had a wide range of soil trace element concentrations, acid soils and a depauperate fauna. They were very poor wildlife habitat because they were dominated by the common reed. Bioassay earthworms exposed to surface soils from three of the five sites died, whereas those exposed to four of five soils collected a meter deep survived, presumably because the deeper, unoxidized soil, was not as acid. Concentrations of Ni and Cr in the biota from each of the sites did not seem to be related to the concentrations of the same elements in soil. Although Pb, Zn and Cu concentrations in biota were correlated with those in soil, the range of concentrations in the biota was quite small compared to that in soil. The concentrations of Pb detected in mice were about as high as the concentrations previously reported in control mice from other studies. Mice from the most contaminated site (530 ppm Pb in soil) contained only slightly more Pb (8 ppm dry wt) than did mice (2-6 ppm dry wt) from sites containing much less Pb (22-92 ppm in soil). Despite the acid soil conditions, very little Cd was incorporated into food chains. Rather, Cd was leaching from the surface soil. We concluded that even the relatively high concentrations of trace elements in the acid dredged material studied did not cause high concentrations of trace elements in the biota. PMID:15092276

  9. Trace elements in soil and biota in confined disposal facilities for dredged material

    USGS Publications Warehouse

    Beyer, W.N.; Miller, G.; Simmers, J.W.

    1990-01-01

    We studied the relation of trace element concentrations in soil to those in house mice (Mus musculus), common reed (Phragmites australis) and ladybugs (Coccinella septempunctata) at five disposal facilities for dredged material. The sites had a wide range of soil trace element concentrations, acid soils and a depauperate fauna. They were very poor wildlife habitat because they were dominated by the common reed. Bioassay earthworms exposed to surface soils from three of the five sites died, whereas those exposed to four of five soils collected a meter deep survived, presumably because the deeper, unoxidized soil, was not as acid. Concentrations of Ni and Cr in the biota from each of the sites did not seem to be related to the concentrations of the same elements in soil. Although Pb, Zn and Cu concentrations in biota were correlated with those in soil, the range of concentrations in the biota was quite small compared to that in soil. The concentrations of Pb detected in mice were about as high as the concentrations previously reported in control mice from other studies. Mice from the most contaminated site (530 ppm Pb in soil) contained only slightly more Pb (8 ppm dry wt) than did mice (2-6 ppm dry wt) from sites containing much less Pb (22-92 ppm in soil). Despite the acid soil conditions, very little Cd was incorporated into food chains. Rather, Cd was leaching from the surface soil. We concluded that even the relatively high concentrations of trace elements in the acid dredged material studied did not cause high, concentrations of trace elements in the biota.

  10. F sorption/desorption on two soils and on different by-products and waste materials.

    PubMed

    Quintáns-Fondo, Ana; Ferreira-Coelho, Gustavo; Paradelo-Núñez, Remigio; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María J; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2016-07-01

    We used batch-type experiments to study F sorption/desorption on a forest soil, a vineyard soil, pyritic material, granitic material, finely and coarsely ground mussel shell, mussel shell calcination ash, oak wood ash, pine-sawdust, slate processing fines, and three different mixtures that included three components: sewage sludge, mussel shell ash, and calcined mussel shell or pine wood ash. The three waste mixtures, forest soil, pyritic material, and shell ash showed high sorption capacity (73-91 % of added F) and low desorption, even when 100 mg F L(-1) was added. All these materials (and to a lower extent wood ash) could be useful to remove F from polluted media (as certain soils, dumping sites, and contaminated waters). The vineyard soil, the granitic material, mussel shell, slate fines, and pine-sawdust were less effective in F removal. In most cases, sorption data fitted better to the Freundlich than to the Langmuir equation. These results can be useful to program the correct management of the soils, by-products, and waste materials assayed, mostly in situations where F concentrations are excessive and F removal should be promoted. PMID:27250088

  11. Retrospective Analysis of NIST Standard Reference Material 1450, Fibrous Glass Board, for Thermal Insulation Measurements

    PubMed Central

    Zarr, Robert R; Heckert, N Alan; Leigh, Stefan D

    2014-01-01

    Thermal conductivity data acquired previously for the establishment of Standard Reference Material (SRM) 1450, Fibrous Glass Board, as well as subsequent renewals 1450a, 1450b, 1450c, and 1450d, are re-analyzed collectively and as individual data sets. Additional data sets for proto-1450 material lots are also included in the analysis. The data cover 36 years of activity by the National Institute of Standards and Technology (NIST) in developing and providing thermal insulation SRMs, specifically high-density molded fibrous-glass board, to the public. Collectively, the data sets cover two nominal thicknesses of 13 mm and 25 mm, bulk densities from 60 kg·m−3 to 180 kg·m−3, and mean temperatures from 100 K to 340 K. The analysis repetitively fits six models to the individual data sets. The most general form of the nested set of multilinear models used is given in the following equation: λ(ρ,T)=a0+a1ρ+a2T+a3T3+a4e−(T−a5a6)2where λ(ρ,T) is the predicted thermal conductivity (W·m−1·K−1), ρ is the bulk density (kg·m−3), T is the mean temperature (K) and ai (for i = 1, 2, … 6) are the regression coefficients. The least squares fit results for each model across all data sets are analyzed using both graphical and analytic techniques. The prevailing generic model for the majority of data sets is the bilinear model in ρ and T. λ(ρ,T)=a0+a1ρ+a2T One data set supports the inclusion of a cubic temperature term and two data sets with low-temperature data support the inclusion of an exponential term in T to improve the model predictions. Physical interpretations of the model function terms are described. Recommendations for future renewals of SRM 1450 are provided. An Addendum provides historical background on the origin of this SRM and the influence of the SRM on external measurement programs. PMID:26601034

  12. Comprehensive Chemical Characterization of Hydrocarbons in NIST Standard Reference Material 2779 Gulf of Mexico Crude Oil.

    PubMed

    Worton, David R; Zhang, Haofei; Isaacman-VanWertz, Gabriel; Chan, Arthur W H; Wilson, Kevin R; Goldstein, Allen H

    2015-11-17

    Comprehensive chemical information is needed to understand the environmental fate and impact of hydrocarbons released during oil spills. However, chemical information remains incomplete because of the limitations of current analytical techniques and the inherent chemical complexity of crude oils. In this work, gas chromatography (GC)-amenable C9-C33 hydrocarbons were comprehensively characterized from the National Institute of Standards and Technology Standard Reference Material (NIST SRM) 2779 Gulf of Mexico crude oil by GC coupled to vacuum ultraviolet photoionization mass spectrometry (GC/VUV-MS), with a mass balance of 68 ± 22%. This technique overcomes one important limitation faced by traditional GC and even comprehensive 2D gas chromatography (GC×GC): the necessity for individual compounds to be chromatographically resolved from one another in order to be characterized. VUV photoionization minimizes fragmentation of the molecular ions, facilitating the characterization of the observed hydrocarbons as a function of molecular weight (carbon number, NC), structure (number of double bond equivalents, NDBE), and mass fraction (mg kg(-1)), which represent important metrics for understanding their fate and environmental impacts. Linear alkanes (8 ± 1%), branched alkanes (11 ± 2%), and cycloalkanes (37 ± 12%) dominated the mass with the largest contribution from cycloalkanes containing one or two rings and one or more alkyl side chains (27 ± 9%). Linearity and good agreement with previous work for a subset of >100 components and for the sum of compound classes provided confidence in our measurements and represents the first independent assessment of our analytical approach and calibration methodology. Another crude oil collected from the Marlin platform (35 km northeast of the Macondo well) was shown to be chemically identical within experimental errors to NIST SRM 2779, demonstrating that Marlin crude is an appropriate surrogate oil for researchers conducting

  13. Single crystal critical dimension reference materials (SCCDRM): process optimization for the next generation of standards

    NASA Astrophysics Data System (ADS)

    Dixson, Ronald G.; Guthrie, William F.; Cresswell, Michael; Allen, Richard A.; Orji, Ndubuisi G.

    2007-03-01

    Critical dimension atomic force microscopes (CD-AFMs) are rapidly gaining acceptance in semiconductor manufacturing metrology. These instruments offer non-destructive three dimensional imaging of structures and can provide a valuable complement to critical dimension scanning electron microscope (CD-SEM) and optical metrology. Accurate CD-AFM metrology, however, is critically dependent upon calibration of the tip width. In response to this need, NIST has developed prototype single crystal critical dimension reference materials (SCCDRMs). In 2004, a new generation of SCCDRMs was released to the Member Companies of SEMATECH - a result of the fruitful partnership between several organizations. These specimens, which are fabricated using a lattice-plane-selective etch on (110) silicon, exhibit near vertical sidewalls and high uniformity and can be used to calibrate CD-AFM tip width to a standard uncertainty of about +/- 1 nm. Following the 2004 release, NIST began work on the "next generation" of SCCDRM standards. A major goal of this thrust was to improve upon the SCCDRM characteristics that impact user-friendliness: the linewidth uniformity and cleanliness. Toward this end, an experiment was designed to further optimize the process conditions. The first round of this experiment was recently completed, and the results show great promise for further improvement of the SCCDRM manufacturing process. Among other observations, we found that the minimum linewidth and linewidth uniformity were primarily sensitive to different factors - and can thus be independently tuned to meet our future goals - which include linewidths as small as 20 nm and a standard uncertainty due to non-uniformity at the +/- 0.5 nm level. Our future work will include a new refining experiment to further optimize the important factors that we have identified, and extension of the methodology to a monolithic 200 mm implementation.

  14. Does thermal carbonization (Biochar) of organic material increase more merits for their amendments of sandy soil?

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Xu, G.; Sun, J. N.; Shao, H. B.

    2014-02-01

    Organic materials (e.g. furfural residue) are generally believed to improve the physical and chemical properties of the soils with low fertility. Recently, biochar have been received more attention as a possible measure to improve the carbon balance and improve soil quality in some degraded soils. However, little is known about their different amelioration of a sandy saline soil. In this study, 56d incubation experiment was conducted to evaluate the influence of furfural and its biochar on the properties of saline soil. The results showed that both furfural and biochar greatly reduced pH, increased soil organic carbon (SOC) content and cation exchange capacity (CEC), and enhanced the available phosphorus (P) in the soil. Furfural is more efficient than biochar in reducing pH: 5% furfural lowered the soil pH by 0.5-0.8 (soil pH: 8.3-8.6), while 5% biochar decreased by 0.25-0.4 due to the loss of acidity in pyrolysis process. With respect to available P, 5% of the furfural addition increased available P content by 4-6 times in comparison to 2-5 times with biochar application. In reducing soil exchangeable sodium percentage (ESP), biochar is slightly superior to furfural because soil ESP reduced by 51% and 43% with 5% furfural and 5% biochar addition at the end of incubation. In addition, no significant differences were observed between furfural and biochar about their capacity to retain N, P in leaching solution and to increase CEC in soil. These facts may be caused by the relatively short incubation time. In general, furfural and biochar have different amendments depending on soil properties: furfural was more effectively to decrease pH and to increase available P, whereas biochar played a more important role in increasing SOC and reducing ESP of saline soil.

  15. Minimizing soil remediation volume through specification of excavation and materials handling procedures

    SciTech Connect

    Oresik, W.L.S.; Otten, M.T.; Nelson, M.D.

    1994-12-31

    The technologies currently available for treating soils contaminated with the explosives 2,4,6-trinitroluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazene (RDX) are both limited and expensive. Therefore, an important consideration in soils remediation is the preparation of construction specifications and contract drawings which limit the volume of soil that will be required to undergo treatment. Construction specifications and contract drawings were developed for the Contaminated Soil Remediation of the Explosives Washout Lagoons at Umatilla Depot Activity (UMDA) with the following primary objectives: (1) limit the volume of soil excavated from the Explosives Washout Lagoons and Explosives Washout Plant Areas, (2) minimize materials handling, and (3) reduce the excavated volume of soil which will undergo treatment.

  16. Arranging Materials and Services in a University Library Reference Area for Effective Use.

    ERIC Educational Resources Information Center

    Franklin, Hugh; And Others

    In fall of 1988, the William Jasper Kerr Library at Oregon State University combined its separate science/technology and social science/humanities reference areas. One year later, the Reference Arrangement Task Force was appointed to evaluate the effectiveness of the new configuration. The Task Force modelled the area with drawings and balsa…

  17. Literature Search, Reference File and Compendium of Instructional Materials for Citizen Education: Final Report.

    ERIC Educational Resources Information Center

    Research for Better Schools, Inc., Philadelphia, PA.

    The report describes a search for instructional materials on citizen education, provides a directory of materials and publishers, and reviews materials. The document is presented in seven sections. Section I describes the search for literature relevant to citizen education. Section II explains that the search scope encompasses materials dealing…

  18. Certified reference materials for testing of the presence/absence of Staphylococcus aureus enterotoxin A (SEA) in cheese.

    PubMed

    Zeleny, Reinhard; Nia, Yacine; Schimmel, Heinz; Mutel, Isabelle; Hennekinne, Jacques-Antoine; Emteborg, Håkan; Charoud-Got, Jean; Auvray, Frédéric

    2016-08-01

    Staphylococcal enterotoxins (SEs) account for a substantial number of food-poisoning outbreaks. European legislation (Commission Regulation 1441/2007) stipulates the reference procedure for SE analysis in milk and dairy products, which is based on extraction, dialysis concentration and immunochemical detection using one of two approved assays (VIDAS(®) SET2, Ridascreen(®) SET Total). However, certified reference materials (CRMs) are lacking to support laboratories in performing reliable detection of Staphylococcus aureus enterotoxin A (SEA) in relevant matrices at sub-nanogram per gram levels. The certification of a set of three reference materials (blank and two SEA-containing materials) for testing of the presence/absence of SEA in cheese is described. The reference procedure was applied in an intercomparison with 15 laboratories, and results were reported in a qualitative manner (presence or absence of SEA in the sample). No false-negative or false-positive results were obtained. The certified values were stated as diagnostic specificity (blank material) or diagnostic sensitivity (SEA-containing materials) and were 100 % in all cases. Stability studies demonstrated suitable material stability when stored cooled or frozen. An in-house study on the recovery of SEA in the cheese materials using a double-sandwich enzyme-linked immunosorbent assay (ELISA) revealed comparable recovery values of around 45 % at the two spiking levels and in both the SEA-containing CRMs as well as blank CRM freshly spiked prior to analysis. The values were also comparable over time and among different analysts. The materials provide valuable support to laboratories for method validation and method performance verification and will increase the reliability of measuring SEA in cheese.

  19. Certified reference materials for testing of the presence/absence of Staphylococcus aureus enterotoxin A (SEA) in cheese.

    PubMed

    Zeleny, Reinhard; Nia, Yacine; Schimmel, Heinz; Mutel, Isabelle; Hennekinne, Jacques-Antoine; Emteborg, Håkan; Charoud-Got, Jean; Auvray, Frédéric

    2016-08-01

    Staphylococcal enterotoxins (SEs) account for a substantial number of food-poisoning outbreaks. European legislation (Commission Regulation 1441/2007) stipulates the reference procedure for SE analysis in milk and dairy products, which is based on extraction, dialysis concentration and immunochemical detection using one of two approved assays (VIDAS(®) SET2, Ridascreen(®) SET Total). However, certified reference materials (CRMs) are lacking to support laboratories in performing reliable detection of Staphylococcus aureus enterotoxin A (SEA) in relevant matrices at sub-nanogram per gram levels. The certification of a set of three reference materials (blank and two SEA-containing materials) for testing of the presence/absence of SEA in cheese is described. The reference procedure was applied in an intercomparison with 15 laboratories, and results were reported in a qualitative manner (presence or absence of SEA in the sample). No false-negative or false-positive results were obtained. The certified values were stated as diagnostic specificity (blank material) or diagnostic sensitivity (SEA-containing materials) and were 100 % in all cases. Stability studies demonstrated suitable material stability when stored cooled or frozen. An in-house study on the recovery of SEA in the cheese materials using a double-sandwich enzyme-linked immunosorbent assay (ELISA) revealed comparable recovery values of around 45 % at the two spiking levels and in both the SEA-containing CRMs as well as blank CRM freshly spiked prior to analysis. The values were also comparable over time and among different analysts. The materials provide valuable support to laboratories for method validation and method performance verification and will increase the reliability of measuring SEA in cheese. PMID:27220526

  20. Determination of the purity of pharmaceutical reference materials by 1H NMR using the standardless PULCON methodology.

    PubMed

    Monakhova, Yulia B; Kohl-Himmelseher, Matthias; Kuballa, Thomas; Lachenmeier, Dirk W

    2014-11-01

    A fast and reliable nuclear magnetic resonance spectroscopic method for quantitative determination (qNMR) of targeted molecules in reference materials has been established using the ERETIC2 methodology (electronic reference to access in vivo concentrations) based on the PULCON principle (pulse length based concentration determination). The developed approach was validated for the analysis of pharmaceutical samples in the context of official medicines control, including ibandronic acid, amantadine, ambroxol and lercanidipine. The PULCON recoveries were above 94.3% and coefficients of variation (CVs) obtained by quantification of different targeted resonances ranged between 0.7% and 2.8%, demonstrating that the qNMR method is a precise tool for rapid quantification (approximately 15min) of reference materials and medicinal products. Generally, the values were within specification (certified values) provided by the manufactures. The results were in agreement with NMR quantification using an internal standard and validated reference HPLC analysis. The PULCON method was found to be a practical alternative with competitive precision and accuracy to the classical internal reference method and it proved to be applicable to different solvent conditions. The method can be recommended for routine use in medicines control laboratories, especially when the availability and costs of reference compounds are problematic.

  1. Determination of the purity of pharmaceutical reference materials by 1H NMR using the standardless PULCON methodology.

    PubMed

    Monakhova, Yulia B; Kohl-Himmelseher, Matthias; Kuballa, Thomas; Lachenmeier, Dirk W

    2014-11-01

    A fast and reliable nuclear magnetic resonance spectroscopic method for quantitative determination (qNMR) of targeted molecules in reference materials has been established using the ERETIC2 methodology (electronic reference to access in vivo concentrations) based on the PULCON principle (pulse length based concentration determination). The developed approach was validated for the analysis of pharmaceutical samples in the context of official medicines control, including ibandronic acid, amantadine, ambroxol and lercanidipine. The PULCON recoveries were above 94.3% and coefficients of variation (CVs) obtained by quantification of different targeted resonances ranged between 0.7% and 2.8%, demonstrating that the qNMR method is a precise tool for rapid quantification (approximately 15min) of reference materials and medicinal products. Generally, the values were within specification (certified values) provided by the manufactures. The results were in agreement with NMR quantification using an internal standard and validated reference HPLC analysis. The PULCON method was found to be a practical alternative with competitive precision and accuracy to the classical internal reference method and it proved to be applicable to different solvent conditions. The method can be recommended for routine use in medicines control laboratories, especially when the availability and costs of reference compounds are problematic. PMID:25215441

  2. Vapor-pressure osmometric study of the molecular weight and aggregation tendency of a reference-soil fulvic acid

    USGS Publications Warehouse

    Marinsky, J.A.; Reddy, M.M.

    1990-01-01

    The molecular weight and aggregation tendency of a reference-soil fulvic acid in Armadale horizon Bh were determined by vapor-pressure osmometry using tetrahydrofuran and water as solvents. With tetrahydrofuran, number-average molecular weight values of 767 ?? 34 and 699 ?? 8 daltons were obtained from two separate sets of measurements. Two sets of measurements with water also yielded values within this range (754 ?? 70 daltons) provided that the fulvic acid concentration in water did not exceed 7 mg ml-1; at higher concentrations (9.1-13.7 mg ml-1) a number-average molecular weight of 956 ?? 25 daltons was resolved, providing evidence of molecular aggregation. Extension of these studies to 80% neutralized fulvic acid showed that a sizeable fraction of the sodium counter ion is not osmotically active.

  3. Feasibility study for producing a carrot/potato matrix reference material for 11 selected pesticides at EU MRL level: material processing, homogeneity and stability assessment.

    PubMed

    Saldanha, Helena; Sejerøe-Olsen, Berit; Ulberth, Franz; Emons, Hendrik; Zeleny, Reinhard

    2012-05-01

    The feasibility for producing a matrix reference material for selected pesticides in a carrot/potato matrix was investigated. A commercially available baby food (carrot/potato-based mash) was spiked with 11 pesticides at the respective EU maximum residue limits (MRLs), and further processed by either freezing or freeze-drying. Batches of some 150 units were produced per material type. First, the materials were assessed for the relative amount of pesticide recovered after processing (ratio of pesticide concentration in the processed material to the initially spiked pesticide concentration). In addition, the materials' homogeneity (bottle-to-bottle variation), and the short-term (1 month) and mid-term (5 months) stability at different temperatures were assessed. For this, an in-house validated GC-EI-MS method operated in the SIM mode with a sample preparation procedure based on the QuEChERS ("quick, easy, cheap, effective, rugged, and safe") principle was applied. Measurements on the frozen material provided the most promising results (smallest analyte losses during production), and also freeze-drying proved to be a suitable alternative processing technique for most of the investigated pesticides. Both the frozen and the freeze-dried material showed to be sufficiently homogeneous for the intended use, and storage at -20°C for 5 months did not reveal any detectable material degradation. The results constitute an important step towards the development of a pesticide matrix reference material. PMID:26434333

  4. Reference Materials for Determination of the Nutrient Composition of Foods: Results from USDA's National Food and Nutrient Analysis Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Certified reference materials (CRMs) play a critical role in validating the accuracy of nutrient data for food samples. A number of available food CRMs of differing matrix composition have assigned concentrations for various nutrients, along with associated uncertainty intervals (UIs) for those valu...

  5. PDQ: Planning and Development of Quality Services in the Schools, Instructional Guide, Student Manual and Reference Materials.

    ERIC Educational Resources Information Center

    Wright, Sandra Raymore

    The instructional guide, student manual, and reference materials were developed by the PDQ Project, Planning and Development of Quality Services in the Schools, an effort by the American Speech-Language-Hearing Association to provide public school personnel working with communication disordered children with information and training related to…

  6. Estimation of the minimum uncertainty of DNA concentration in a genetically modified maize sample candidate certified reference material.

    PubMed

    Prokisch, J; Zeleny, R; Trapmann, S; Le Guern, L; Schimmel, H; Kramer, G N; Pauwels, J

    2001-08-01

    Homogeneity testing and the determination of minimum sample mass are an important part of the certification of reference materials. The smallest theoretically achievable uncertainty of certified concentration values is limited by the concentration distribution of analyte in the different particle size fractions of powdered biological samples. This might be of special importance if the reference material is prepared by dry mixing, a dilution technique which is used for the production of the new and third generation of genetically modified (GMO) plant certified reference materials. For the production of dry mixed PMON 810 maize reference material a computer program was developed to calculate the theoretically smallest uncertainty for a selected sample intake. This model was used to compare three differently milled maize samples, and the effect of dilution on the uncertainty of the DNA content of GMO maize was estimated as well. In the case of a 50-mg sample mass the lowest achievable standard deviation was 2% for the sample containing 0.1% GMO and the minimum deviation was less than 0.5% for the sample containing 5% GMO. PMID:11569879

  7. Doorways II: Community Counselor Reference Materials. On School-Related Gender-Based Violence Prevention and Response

    ERIC Educational Resources Information Center

    US Agency for International Development, 2009

    2009-01-01

    The Doorways training program was designed by the U.S. Agency for International Development (USAID)-funded Safe Schools Program (Safe Schools) to enable teachers, community members and students to prevent and respond to school-related gender-based violence (SRGBV). This booklet, "Doorways II: Community Counselor Reference Materials on…

  8. COMPARISON OF PULMONARY RESPONSES TO AUTOMOBILE-GENERATED AND NIST STANDARD REFERENCE MATERIAL DIESEL PARTICULATE EMISSIONS IN MICE

    EPA Science Inventory

    COMPARISON OF PULMONARY RESPONSES TO AUTOMOBILE-GENERATED AND NIST STANDARD REFERENCE MATERIAL DIESEL PARTICULATE EMISSIONS IN MICE. P. Singh1, C.A.J. Dick2, J. Richards3, M.J. Daniels3, and M.I. Gilmour3. 1NCSU, Raleigh, NC, 2UNC, Chapel Hill, NC and 3 USEPA, ORD, NHEERL, (ETD,...

  9. Development of a genomic DNA reference material panel for myotonic dystrophy type 1 (DM1) genetic testing.

    PubMed

    Kalman, Lisa; Tarleton, Jack; Hitch, Monica; Hegde, Madhuri; Hjelm, Nick; Berry-Kravis, Elizabeth; Zhou, Lili; Hilbert, James E; Luebbe, Elizabeth A; Moxley, Richard T; Toji, Lorraine

    2013-07-01

    Myotonic dystrophy type 1 (DM1) is caused by expansion of a CTG triplet repeat in the 3' untranslated region of the DMPK gene that encodes a serine-threonine kinase. Patients with larger repeats tend to have a more severe phenotype. Clinical laboratories require reference and quality control materials for DM1 diagnostic and carrier genetic testing. Well-characterized reference materials are not available. To address this need, the Centers for Disease Control and Prevention-based Genetic Testing Reference Material Coordination Program, in collaboration with members of the genetic testing community, the National Registry of Myotonic Dystrophy and Facioscapulohumeral Muscular Dystrophy Patients and Family Members, and the Coriell Cell Repositories, has established and characterized cell lines from patients with DM1 to create a reference material panel. The CTG repeats in genomic DNA samples from 10 DM1 cell lines were characterized in three clinical genetic testing laboratories using PCR and Southern blot analysis. DMPK alleles in the samples cover four of five DM1 clinical categories: normal (5 to 34 repeats), mild (50 to 100 repeats), classical (101 to 1000 repeats), and congenital (>1000 repeats). We did not identify or establish Coriell cell lines in the premutation range (35 to 49 repeats). These samples are publicly available for quality control, proficiency testing, test development, and research and should help improve the accuracy of DM1 testing. PMID:23680132

  10. Estimation of the minimum uncertainty of DNA concentration in a genetically modified maize sample candidate certified reference material.

    PubMed

    Prokisch, J; Zeleny, R; Trapmann, S; Le Guern, L; Schimmel, H; Kramer, G N; Pauwels, J

    2001-08-01

    Homogeneity testing and the determination of minimum sample mass are an important part of the certification of reference materials. The smallest theoretically achievable uncertainty of certified concentration values is limited by the concentration distribution of analyte in the different particle size fractions of powdered biological samples. This might be of special importance if the reference material is prepared by dry mixing, a dilution technique which is used for the production of the new and third generation of genetically modified (GMO) plant certified reference materials. For the production of dry mixed PMON 810 maize reference material a computer program was developed to calculate the theoretically smallest uncertainty for a selected sample intake. This model was used to compare three differently milled maize samples, and the effect of dilution on the uncertainty of the DNA content of GMO maize was estimated as well. In the case of a 50-mg sample mass the lowest achievable standard deviation was 2% for the sample containing 0.1% GMO and the minimum deviation was less than 0.5% for the sample containing 5% GMO.

  11. Development of a reference material for Staphylococcus aureus enterotoxin A in cheese: feasibility study, processing, homogeneity and stability assessment.

    PubMed

    Zeleny, R; Emteborg, H; Charoud-Got, J; Schimmel, H; Nia, Y; Mutel, I; Ostyn, A; Herbin, S; Hennekinne, J-A

    2015-02-01

    Staphylococcal food poisoning is caused by enterotoxins excreted into foods by strains of staphylococci. Commission Regulation 1441/2007 specifies thresholds for the presence of these toxins in foods. In this article we report on the progress towards reference materials (RMs) for Staphylococcal enterotoxin A (SEA) in cheese. RMs are crucial to enforce legislation and to implement and safeguard reliable measurements. First, a feasibility study revealed a suitable processing procedure for cheese powders: the blank material was prepared by cutting, grinding, freeze-drying and milling. For the spiked material, a cheese-water slurry was spiked with SEA solution, freeze-dried and diluted with blank material to the desired SEA concentration. Thereafter, batches of three materials (blank; two SEA concentrations) were processed. The materials were shown to be sufficiently homogeneous, and storage at ambient temperature for 4weeks did not indicate degradation. These results provide the basis for the development of a RM for SEA in cheese. PMID:25172706

  12. Development of Low Cost Soil Stabilization Using Recycled Material

    NASA Astrophysics Data System (ADS)

    Ahmad, F.; Yahaya, A. S.; Safari, A.

    2016-07-01

    Recycled tyres have been used in many geotechnical engineering projects such as soil improvement, soil erosion and slope stability. Recycled tyres mainly in chip and shredded form are highly compressible under low and normal pressures. This characteristic would cause challenging problems in some applications of soil stabilization such as retaining wall and river bank projects. For high tensile stress and low tensile strain the use of fiberglass would be a good alternative for recycled tyre in some cases. To evaluate fiberglass as an alternative for recycled tyre, this paper focused on tests of tensile tests which have been carried out between fiberglass and recycled tyre strips. Fibreglass samples were produced from chopped strand fibre mat, a very low-cost type of fibreglass, which is cured by resin and hardener. Fibreglass samples in the thickness of 1 mm, 2 mm, 3 mm and 4 mm were developed 100 mm x 300 mm pieces. It was found that 3 mm fibreglass exhibited the maximum tensile load (MTL) and maximum tensile stress (MTS) greater than other samples. Statistical analysis on 3 mm fibreglass indicated that in the approximately equal MTL fibreglass samples experienced 2% while tyre samples experienced 33.9% ultimate tensile strain (UTST) respectively. The results also showed an approximately linear relationship between stress and strain for fibreglass samples and Young's modulus (E), ranging from 3581 MPa to 4728 MPa.

  13. Microwave method for reference-plane-invariant and thickness-independent permittivity determination of liquid materials.

    PubMed

    Hasar, U C; Kaya, Y; Bute, M; Barroso, J J; Ertugrul, M

    2014-01-01

    An attractive transmission-reflection method based on reference-plane invariant and thickness-independent expressions has been proposed for accurate and unique retrieval of complex permittivity of dielectric liquid samples. The method uses both branch-index-independent expressions and a restricted solution set for determining unique and fast complex permittivities. A 2D graphical method has been applied to demonstrate the operation and validation of the proposed method. A uncertainty analysis has been performed to monitor how the accuracy of the proposed method can be improved by a correct selection of sample holder properties. Scattering parameter measurements of two tested reference liquids (distilled water and methanol) have been carried out for comparison of various techniques with the proposed one when the reference-planes and sample thickness are not precisely known. We note from the comparison that whereas other techniques are seriously affected by imprecise knowledge of both reference-planes and sample thickness, the proposed method removes this restriction.

  14. Mineral materials as feasible amendments to stabilize heavy metals in polluted urban soils.

    PubMed

    Zhang, Mingkui; Pu, Jincheng

    2011-01-01

    Four minerals, agricultural limestone (AL), rock phosphate (RP), palygorskite (PG), and calcium magnesium phosphate (CMP), were evaluated by means of chemical fractions of heavy metals in soils and concentrations of heavy metals in leachates from columns to determine their ability to stabilize heavy metals in polluted urban soils. Two urban soils (calcareous soil and acidic soil) polluted with cadmium, copper, zinc and lead were selected and amended in the laboratory with the mineral materials) for 12 months. Results indicated that application of the mineral materials reduced exchangeable metals in the sequence of Pb, Cd > Cu > Zn. The reduction of exchangeable fraction of heavy metals in the soils amended with different mineral materials followed the sequence of CMP, PG > AL > RP. Reductions of heavy metals leached were based on comparison with cumulative totals of heavy metals eluted through 12 pore volumes from an untreated soil. The reductions of the metals eluted from the calcareous soil amended with the RP, AL, PG and CMP were 1.98%, 38.89%, 64.81% and 75.93% for Cd, 8.51%, 40.42%, 60.64% and 55.32% for Cu, 1.76%, 52.94%, 70.00% and 74.12% for Pb, and 28.42%, 52.74%, 64.38% and 49.66% for Zn. Those from the acidic soil amended with the CMP, PG, AL, and RP were 25.65%, 68.06%, 78.01% and 79.06% for Cd, 26.56%, 49.64%, 43.40% and 34.68% for Cu, 44.44%, 33.32%, 61.11% and 69.44% for Pb, and 18.46%, 43.77%, 41.98% and 40.68% for Zn. The CMP and PG treatments were superior to the AL and RP for stabilizing heavy metals in the polluted urban soils.

  15. How physical alteration of technic materials affects mobility and phytoavailabilty of metals in urban soils?

    PubMed

    El Khalil, Hicham; Schwartz, Christophe; El Hamiani, Ouafae; Sirguey, Catherine; Kubiniok, Jochen; Boularbah, Ali

    2016-06-01

    One fundamental characteristic distinguishing urban soils from natural soils is the presence of technic materials or artefacts underlining the influence of human activity. These technic materials have different nature (organic or inorganic) and origins. They contribute to the enrichment of the soil solution by metallic trace elements. The present study aims to determine the effect of physical alteration of the technic coarse fraction on the bioavailability of metallic trace elements in urban Technosols. In general, results show that physical alteration increases the metallic trace elements water extractible concentrations of technic materials. The ability of lettuce to accumulate metallic trace elements, even at low concentrations, underlines the capacity of technic materials to contaminate the anthropised soil solution by bioavailable metals. The highest metal levels, accumulated by the various organs of the lettuce (leaves and roots), were measured in plants grown in presence of metallic particles mixtures. This indicates that the majority of metallic trace elements released by this technic constituent is bioavailable and explains the low plant biomass obtained. The abundant part of metallic trace elements released by the other technic constituents (building materials, bones, wood, plastic and fabric-paper) remains less bioavailable. Under anthropised soil conditions, technic materials have a significant effect on the metallic trace elements behavior. They impact the flow of these metallic elements in Technosols, which can increase their bioavailability and, therefore, the contamination of the food chain. PMID:26999750

  16. Use of Biochar from the Pyrolysis of Waste Organic Material as a Soil Amendment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biochar is a charcoal-like material produced by the thermochemical pyrolysis of biomass materials. It is being considered as a potentially significant means of storing carbon for long periods to mitigate greenhouse gases. Much of the interest comes from studies of Amazonian soils that appear to have...

  17. Metrological aspects related to stable isotope reference materials: the traceability concept and uncertainty evaluation scheme supporting every day practice.

    NASA Astrophysics Data System (ADS)

    Assonov, Sergey; Groening, Manfred; Fajgelj, Ales

    2016-04-01

    The worldwide metrological comparability of stable isotope measurement results is presently achieved by linking them to the conventional delta scales. Delta scales are realized by scale defining reference materials, most of them being supplied by the IAEA (examples are VSMOW2 & SLAP2). In fact, these reference materials are artefacts, characterized by a network of laboratories using the current best measurement practice. In reality any measurement result is linked to the scale via reference materials (RMs) in use. Any RMs is traceable to the highest-level RMs which define the scale; this is valid not only for international RMs (mostly secondary RMs like IAEA-CH-7, NBS22) but for any lab standard calibrated by users. This is a basic of measurement traceability. The traceability scheme allows addressing both the comparability and long-term compatibility of measurement results. Correspondingly, the uncertainty of any measurement result has to be propagated up to the scale level. The uncertainty evaluation should include (i) the uncertainty of the RMs in use; (ii) the analytical uncertainty of the materials used in calibration runs performed at the user laboratory; (iii) the reproducibility on results obtained on sample material; (iv) the uncertainty of corrections applied (memory, drift, etc). Besides these, there may be other uncertainty components of to be considered. The presentation will illustrate the metrological concepts involved (comparability, traceability etc) and give a generic scheme for the uncertainty evaluation.

  18. Sodic hazard: the effect of SAR and salinity in soils and overburden materials

    SciTech Connect

    Jurinak, J.J.; Amrhein, C.; Wagenet, R.J.

    1984-03-01

    The authors studied the effect of salinity and sodium adsorption ratio (SAR) on the modified Gapon selectivity coefficient (k/sub g/') using Yolo loam soil and two (sodic) coal mine overburden materials designated surface and deep. The SAR treatments varied in value from 5 to 80 (mmol/L)/sup 1/2/ in an electrolyte solution (NaCl + CaCl/sub 2/) concentration range of 10 to 500 meq/L. When all treatment effects were combined, the k/sub g/' values were 0.0097, 0.0087, and 0.0079 (mmol/L)/sub -1/2/ for Yolo loam, surface, and deep overburden, respectively. In contrast to the other two systems, the deep overburden exhibited a steadily declining value of k/sub g/' (0.014 to 0.0055 (mmol/L)/sup -1/2/ with increasing electrolyte concentration. In all cases the k/sub g/' values were found to be less than the commonly used value of 0.015 (mmol/L)/sup -1/2/. 13 references, 5 figures, 7 tables.

  19. Development of a candidate reference material for adventitious virus detection in vaccine and biologicals manufacturing by deep sequencing

    PubMed Central

    Mee, Edward T.; Preston, Mark D.; Minor, Philip D.; Schepelmann, Silke; Huang, Xuening; Nguyen, Jenny; Wall, David; Hargrove, Stacey; Fu, Thomas; Xu, George; Li, Li; Cote, Colette; Delwart, Eric; Li, Linlin; Hewlett, Indira; Simonyan, Vahan; Ragupathy, Viswanath; Alin, Voskanian-Kordi; Mermod, Nicolas; Hill, Christiane; Ottenwälder, Birgit; Richter, Daniel C.; Tehrani, Arman; Jacqueline, Weber-Lehmann; Cassart, Jean-Pol; Letellier, Carine; Vandeputte, Olivier; Ruelle, Jean-Louis; Deyati, Avisek; La Neve, Fabio; Modena, Chiara; Mee, Edward; Schepelmann, Silke; Preston, Mark; Minor, Philip; Eloit, Marc; Muth, Erika; Lamamy, Arnaud; Jagorel, Florence; Cheval, Justine; Anscombe, Catherine; Misra, Raju; Wooldridge, David; Gharbia, Saheer; Rose, Graham; Ng, Siemon H.S.; Charlebois, Robert L.; Gisonni-Lex, Lucy; Mallet, Laurent; Dorange, Fabien; Chiu, Charles; Naccache, Samia; Kellam, Paul; van der Hoek, Lia; Cotten, Matt; Mitchell, Christine; Baier, Brian S.; Sun, Wenping; Malicki, Heather D.

    2016-01-01

    Background Unbiased deep sequencing offers the potential for improved adventitious virus screening in vaccines and biotherapeutics. Successful implementation of such assays will require appropriate control materials to confirm assay performance and sensitivity. Methods A common reference material containing 25 target viruses was produced and 16 laboratories were invited to process it using their preferred adventitious virus detection assay. Results Fifteen laboratories returned results, obtained using a wide range of wet-lab and informatics methods. Six of 25 target viruses were detected by all laboratories, with the remaining viruses detected by 4–14 laboratories. Six non-target viruses were detected by three or more laboratories. Conclusion The study demonstrated that a wide range of methods are currently used for adventitious virus detection screening in biological products by deep sequencing and that they can yield significantly different results. This underscores the need for common reference materials to ensure satisfactory assay performance and enable comparisons between laboratories. PMID:26709640

  20. Observation of anomalous behavior in the thermal and electrical conductivity of a standard reference material SRM-735

    NASA Astrophysics Data System (ADS)

    Goldratt, E.; Greenfield, A. J.

    1982-07-01

    Measurements have been carried out over the temperature range 360-480 K of both the thermal conductivity κ(T) and the electrical resistivity ρ(T) for the austenitic stainless steel material chosen by the U.S. National Bureau of Standards as the Standard Reference Material for these two properties in the temperature range 4-1200 K. These measurements show a ripple in κ(T) vs. T centered at 410 K. The amplitude of the observed ripple is within the ±5% experimental scatter of previous data. Measurements of κ(T) for ordinary 304 stainless steel over the same temperature range show no sign of such a ripple. Measurements of the electrical resistivity of the Standard Reference Material also show an unusual structure centered at 410 K.