Science.gov

Sample records for geological reference materials

  1. 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.

  2. 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.

  3. 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

  4. Platinum stable isotope analysis of geological standard reference materials by double-spike MC-ICPMS.

    PubMed

    Creech, J B; Baker, J A; Handler, M R; Bizzarro, M

    2014-01-10

    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 (196)Pt-(198)Pt 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 δ(198)Pt (permil difference in the (198)Pt/(194)Pt 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 δ(198)Pt values with offsets of up to 0.4‰ from the IRMM-010 standard, which are readily resolved with this technique. These

  5. 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

  6. 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.

  7. 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.

  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. 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.

  10. Choosing optimal exposure times for XRF core-scanning: Suggestions based on the analysis of geological reference materials

    NASA Astrophysics Data System (ADS)

    Huang, Jyh-Jaan; Löwemark, Ludvig; Chang, Queenie; Lin, Tzu-Yu; Chen, Huei-Fen; Song, Sheng-Rong; Wei, Kuo-Yen

    2016-04-01

    X-ray fluorescence (XRF) core-scanning is a fast and nondestructive technique to assess elemental variations of unprocessed sediments. However, although the exposure time of XRF-scanning directly affects the scanning counts and total measurement time, only a few studies have considered the influence of exposure time during the scan. How to select an optimal exposure time to achieve reliable results and reduce the total measurement time is an important issue. To address this question, six geological reference materials from the Geological Survey of Japan (JLK-1, JMS-1, JMS-2, JSD-1, JSD-2, and JSD-3) were scanned by the Itrax-XRF core scanner using the Mo- and the Cr-tube with different exposure times to allow a comparison of scanning counts with absolute concentrations. The regression lines and correlation coefficients of elements that are generally used in paleoenvironmental studies were examined for the different exposure times and X-ray tubes. The results show that for those elements with relatively high concentrations or high detectability, the correlation coefficients are higher than 0.90 for all exposure times. In contrast, for the low detectability or low concentration elements, the correlation coefficients are relatively low, and improve little with increased exposure time. Therefore, we suggest that the influence of different exposure times is insignificant for the accuracy of the measurements. Thus, caution must be taken when interpreting the results of elements with low detectability, even when the exposure times are long and scanning counts are reasonably high.

  11. [Determination of Sb and Bi in 24 international geological reference materials by using pressurized acid digestion-ICP-MS].

    PubMed

    Hu, Zhao-chu; Gao, Shan; Liu, Xiao-ming; Yuan, Hong-lin; Liu, Ye; Diwu, Chun-rong

    2007-12-01

    The authors studied in detail the memory effect of Bi, Sb, As and Te in ICP-MS. The produced memory effects of these element were in the order of Bi>Sb>Te>As. Bi was seriously adsorbed by the polypropylene sample storing bottle and the sample introduction system in the low nitric acid medium (0.01%-1% HNO3). The washout effect of 0.1% HF was found to be better than those of 6% HNO3 and 0.1% HClO4. Under the given experiment conditions, the instrumental limit of detection was 0.001 and 0.0001 ng x mL(-1) for Sb and Bi, respectively. The authors report the determination of Sb and Bi in 24 international geological reference materials by using pressurized acid digestion-ICP-MS (including AGV-2, BHVO-2, BCR-2, etc.). Most of the results were found to be in reasonable agreement with the reported values in the literature. The authors' determined values of Sb for GSR-1 (granite; 0.30 microg x g(-1)) and JP-1 (peridotite; 0.045 microg x g(-1)) are obviously higher than those reported values. This is attributed to the efficient pressurized acid digestion, which is generally much more efficient than conventional wet digestions for insoluble minerals.

  12. 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.

  13. Bulk Site Reference Materials

    SciTech Connect

    Barich, J.J. III; Jones, R.R. Sr.

    1996-12-31

    The selection, manufacture and use of Bulk Site Reference Materials (BSRMs) at hazardous waste sites is discussed. BSRMs are useful in preparing stabilization/solidification (S/S) formulations for soils, ranking competing S/S processes, comparing S/S alternatives to other technologies, and in interpreting data from different test types. BSRMs are large volume samples that are representative of the physical and chemical characteristics of a site soil, and that contain contaminants at reasonably high levels. A successful BSRM is extremely homogeneous and well-characterized. While not representative of any point on the site, they contain the contaminants of the site in the matrices of the site. Design objectives for a BSRM are to produce a material that (1) maintains good fidelity to site matrices and contaminants, and (2) exhibits the lowest possible relative standard deviation.

  14. Neutron Absorption in Geological Material

    NASA Astrophysics Data System (ADS)

    Løvhøiden, G.; Andersen, E.

    1990-01-01

    Thermal neutron absorption cross section of geological samples is determined with the steady state neutron source method. Cross section measurements of North Sea sediments demonstrate that also materials with high contents of clay minerals may be investigated with the steady state method.

  15. Reference design description for a geologic repository: Revision 01

    SciTech Connect

    1997-09-01

    This document describes the current design expectations for a potential geologic repository that could be located at Yucca Mountain in Nevada. This Reference Design Description (RDD) looks at the surface and subsurface repository and disposal container design. Additionally, it reviews the expected long-term performance of the potential repository. In accordance with current legislation, the reference design for the potential repository does not include an interim storage option. The reference design presented allows the disposal of highly radioactive material received from government-owned spent fuel custodian sites; produces high-level waste sites, and commercial spent fuel sites. All design elements meet current federal, state, and local regulations governing the disposal of high-level radioactive waste and protection of the public and the environment. Due to the complex nature of developing a repository, the design will be created in three phases to support Viability Assessment, License Application, and construction. This document presents the current reference design. It will be updated periodically as the design progresses. Some of the details presented here may change significantly as more cost-effective solutions, technical advancements, or changes to requirements are identified.

  16. Infrared Analysis of Geological Materials.

    ERIC Educational Resources Information Center

    Brown, Alan; Clark, E. Roy

    1980-01-01

    Describes the infrared analysis of geological specimens which can form the basis of a laboratory exercise, allowing some minerals to be identified by "fingerprint" technique. Students can gain insight into the concept of symmetry and environment around an atom. (Author/SA)

  17. Health benefits of geologic materials and geologic processes

    USGS Publications Warehouse

    Finkelman, R.B.

    2006-01-01

    The reemerging field of Medical Geology is concerned with the impacts of geologic materials and geologic processes on animal and human health. Most medical geology research has been focused on health problems caused by excess or deficiency of trace elements, exposure to ambient dust, and on other geologically related health problems or health problems for which geoscience tools, techniques, or databases could be applied. Little, if any, attention has been focused on the beneficial health effects of rocks, minerals, and geologic processes. These beneficial effects may have been recognized as long as two million years ago and include emotional, mental, and physical health benefits. Some of the earliest known medicines were derived from rocks and minerals. For thousands of years various clays have been used as an antidote for poisons. "Terra sigillata," still in use today, may have been the first patented medicine. Many trace elements, rocks, and minerals are used today in a wide variety of pharmaceuticals and health care products. There is also a segment of society that believes in the curative and preventative properties of crystals (talismans and amulets). Metals and trace elements are being used in some of today's most sophisticated medical applications. Other recent examples of beneficial effects of geologic materials and processes include epidemiological studies in Japan that have identified a wide range of health problems (such as muscle and joint pain, hemorrhoids, burns, gout, etc.) that may be treated by one or more of nine chemically distinct types of hot springs, and a study in China indicating that residential coal combustion may be mobilizing sufficient iodine to prevent iodine deficiency disease. ?? 2006 MDPI. All rights reserved.

  18. Flameless atomic-absorption determination of gold in geological materials

    USGS Publications Warehouse

    Meier, A.L.

    1980-01-01

    Gold in geologic material is dissolved using a solution of hydrobromic acid and bromine, extracted with methyl isobutyl ketone, and determined using an atomic-absorption spectrophotometer equipped with a graphite furnace atomizer. A comparison of results obtained by this flameless atomic-absorption method on U.S. Geological Survey reference rocks and geochemical samples with reported values and with results obtained by flame atomic-absorption shows that reasonable accuracy is achieved with improved precision. The sensitivity, accuracy, and precision of the method allows acquisition of data on the distribution of gold at or below its crustal abundance. ?? 1980.

  19. 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.

  20. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference into... the availability of this material at NARA, call 202-741-6030, or go to:...

  1. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have been... information on the availability of this material at NARA, call 202-741-6030, or go to:...

  2. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Reference materials. 1042.910 Section... Other Reference Information § 1042.910 Reference materials. Documents listed in this section have been... information on the availability of this material at NARA, call 202-741-6030, or go to:...

  3. 40 CFR 94.5 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Reference materials. 94.5 Section 94.5... Compression-Ignition Marine Engines § 94.5 Reference materials. We have incorporated by reference the... availability of this material at NARA, call 202-741-6030, or go to:...

  4. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Reference materials. 1043.100 Section... § 1043.100 Reference materials. Documents listed in this section have been incorporated by reference into... the availability of this material at NARA, call 202-741-6030, or go to:...

  5. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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 into... the availability of this material at NARA, call 202-741-6030, or go to:...

  6. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 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 been... information on the availability of this material at NARA, call 202-741-6030, or go to:...

  7. 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.

  8. 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.

  9. Biological and environmental reference materials: Update 1996

    NASA Astrophysics Data System (ADS)

    Roelandts, Iwan

    1997-07-01

    The present column lists additional biological and environmental reference samples. Organs, tissues, body fluids, plant materials, foods, fuels, ashes, dusts, particulate matter, gas mixtures, oils, soils, sediments, sludges and waters have been considered. Three tables are included that provide an easy-to-use survey. The following information is covered: the name of the material, the sample code, the producer, the reference to certification, the names and addresses of the suppliers from whom the reference material may be obtained, and specific remarks.

  10. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (1) ASTM material. The following table sets forth material from the American Society for Testing and... materials may be obtained from American Society for Testing and Materials, 1916 Race St., Philadelphia, PA... forth material from the Society of Automotive Engineers which has been incorporated by reference....

  11. Pilot study for U.S. Geological Survey Standard Reference Water Samples for pesticides

    USGS Publications Warehouse

    Friedman, L.C.; Fishman, M. J.; Boyle, D.K.

    1984-01-01

    The U. S. Geological Survey has been preparing and maintaining a library of standard reference water samples for inorganic constituents for 19 years. Recently, a pilot study was conducted to see if the reference-sample program could be expanded to include pesticides and other organic materials. Two samples containing organochlorine and organophosphorus insecticides, and chlorophenoxy acid herbicides were distributed to a number of laboratories in the United States. One of the samples also contained polychlorinated biphenyls. Interlaboratory data obtained from these round robin studies are presented with intralaboratory information on long-term stability.

  12. Reference design description for a geologic repository. Revision 02

    SciTech Connect

    1999-01-01

    This Reference Design Description explains the current design for a potential geologic repository that may be located at Yucca Mountain in Nevada. It describes the proposed design for a surface facility, subsurface repository, and waste packaging; it also presents the current design of the key engineering systems for the final four phases: operations, monitoring, closure, and postclosure. In addition, this Reference Design Description reviews the expected long-term performance of the potential repository. In accordance with current law, this design does not include an interim storage option. This document has six major sections. Section 1 describes the physical layout of the proposed repository. The second section describes the 4-phase evolution of the development of the proposed repository. Section 3 describes the reception of waste from offsite locations. The fourth section details the various systems that will package the waste and move it below ground as well as safety monitoring and closure. Section 5 describes the systems (both physical and analytical) that ensure continued safety after closure. The final section offers design options that may be adopted to increase the margin of safety.

  13. Ultrasonic compaction of granular geological materials.

    PubMed

    Feeney, Andrew; Sikaneta, Sakalima; Harkness, Patrick; Lucas, Margaret

    2017-04-01

    It has been shown that the compaction of granular materials for applications such as pharmaceutical tableting and plastic moulding can be enhanced by ultrasonic vibration of the compaction die. Ultrasonic vibrations can reduce the compaction pressure and increase particle fusion, leading to higher strength products. In this paper, the potential benefits of ultrasonics in the compaction of geological granular materials in downhole applications are explored, to gain insight into the effects of ultrasonic vibrations on compaction of different materials commonly encountered in sub-sea drilling. Ultrasonic vibrations are applied, using a resonant 20kHz compactor, to the compaction of loose sand and drill waste cuttings derived from oolitic limestone, clean quartz sandstone, and slate-phyllite. For each material, a higher strain for a given compaction pressure was achieved, with higher sample density compared to that in the case of an absence of ultrasonics. The relationships between the operational parameters of ultrasonic vibration amplitude and true strain rate are explored and shown to be dependent on the physical characteristics of the compacting materials.

  14. 40 CFR 1066.710 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Practice for Measuring Fuel Economy and Emissions of Hybrid-Electric and Conventional Heavy-Duty Vehicles, Issued September 2002, IBR approved for § 1066.501. (c) National Institute of Standards and Technology... VEHICLE-TESTING PROCEDURES Definitions and Other Reference Material § 1066.710 Reference materials....

  15. 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

  16. Precise rare earth analysis of geological materials

    SciTech Connect

    Laul, J.C.; Wogman, N.A.

    1982-01-01

    Rare earth element (REE) concentrations are very informative in revealing chemical fractionation processs in geological systems. The REE's (La-Lu) behavior is characteristic of various primary and secondary minerals which comprise a rock. The REE's contents and their patterns provide a strong fingerprint in distinguishing among various rock types and in understanding the partial melting and/or fractional crystallization of the source region. The REE contents in geological materials are usually at trace levels. To measure all the REE at such levels, radiochemical neutron activation analysis (RNAA) has been used with a REE group separation scheme. To maximize detection sensitivites for individual REE, selective ..gamma..-ray/x-ray measurements have been made using normal Ge(Li) and low-energy photon detectors (LEPD), and Ge(Li)-NaI(Tl) coincidence-noncoincidence spectrometer systems. Using these detection methods an individual REE can be measured at or below the ppB levels; chemical yields of the REE are determined by reactivation.

  17. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Reference material. 171.7 Section 171.7 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS GENERAL INFORMATION,...

  18. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Reference material. 171.7 Section 171.7 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS GENERAL INFORMATION,...

  19. 49 CFR 171.7 - Reference material.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Materials Standards, East Building, PHH-10, 1200 New Jersey Avenue SE., Washington, DC 20590-0001. For... Materials Systems (BOE), Association of American Railroads, American Railroads Building, 50 F Street NW... 49 Transportation 2 2013-10-01 2013-10-01 false Reference material. 171.7 Section...

  20. Development of solid thorium-232 reference materials

    NASA Astrophysics Data System (ADS)

    Engelder, P. R.; Donivan, S.; Chessmore, R. B.

    1985-05-01

    Thorium-232 reference materials with a matrix similar to soil and uranium-mill tailings are necessary for ensuring uniform standardization among measurements performed by remedial-action contractors. Some 200 pounds each of three different concentrations of Th-232 reference material were prepared by diluting a thorium ore with soil. Target values for Th-232 content were 70, 30, and 10 pCi/q. The recommended thorium-232 concentrations for the three reference materials are 71.2 + or - 2.0 pCi/g, 30.5 + or - 0.6 pCi/g, and 10.2 + or - 0.3 pCi/g.

  1. A new river sediment standard reference material.

    PubMed

    Epstein, M S; Diamondstone, B I; Gills, T E

    1989-01-01

    The collection, processing and certification of a new sediment Standard Reference Material (SRM), SRM 2704, is described. Collected from the bottom of the Buffalo River in New York State during the fall of 1986, SRM 2704 is certified for 25 elements with information provided on another 22 elements. Improvements in analytical methods as well as the application of well-defined quality-control procedures for collection, processing and analysis have resulted in a reference material that is more completely characterized than previous NIST sediment reference materials.

  2. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....116; 90.509. (2) SAE material. The following table sets forth material from the Society of Automotive...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September 1991, Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations and Acronyms 90.114 SAE...

  3. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....116; 90.509. (2) SAE material. The following table sets forth material from the Society of Automotive...., Warrendale, PA 15096-0001. Document number and name 40 CFR part 90 reference SAE J1930 September 1991, Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations and Acronyms 90.114 SAE...

  4. 40 CFR 89.6 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...” 89.120; 89.207; 89.509. (2) SAE material. The following table sets forth material from the Society of... Commonwealth Dr., Warrendale, PA 15096-0001. Document number and name 40 CFR part 89 reference SAE J244 June 83: Recommended Practice for Measurement of Intake Air or Exhaust Gas Flow of Diesel Engines 89.416-96 SAE...

  5. 40 CFR 89.6 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...” 89.120; 89.207; 89.509. (2) SAE material. The following table sets forth material from the Society of... Commonwealth Dr., Warrendale, PA 15096-0001. Document number and name 40 CFR part 89 reference SAE J244 June 83: Recommended Practice for Measurement of Intake Air or Exhaust Gas Flow of Diesel Engines 89.416-96 SAE...

  6. 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...

  7. Predictive modeling of terrestrial radiation exposure from geologic materials

    NASA Astrophysics Data System (ADS)

    Haber, Daniel A.

    Aerial gamma ray surveys are an important tool for national security, scientific, and industrial interests in determining locations of both anthropogenic and natural sources of radioactivity. There is a relationship between radioactivity and geology and in the past this relationship has been used to predict geology from an aerial survey. The purpose of this project is to develop a method to predict the radiologic exposure rate of the geologic materials in an area by creating a model using geologic data, images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), geochemical data, and pre-existing low spatial resolution aerial surveys from the National Uranium Resource Evaluation (NURE) Survey. Using these data, geospatial areas, referred to as background radiation units, homogenous in terms of K, U, and Th are defined and the gamma ray exposure rate is predicted. The prediction is compared to data collected via detailed aerial survey by our partner National Security Technologies, LLC (NSTec), allowing for the refinement of the technique. High resolution radiation exposure rate models have been developed for two study areas in Southern Nevada that include the alluvium on the western shore of Lake Mohave, and Government Wash north of Lake Mead; both of these areas are arid with little soil moisture and vegetation. We determined that by using geologic units to define radiation background units of exposed bedrock and ASTER visualizations to subdivide radiation background units of alluvium, regions of homogeneous geochemistry can be defined allowing for the exposure rate to be predicted. Soil and rock samples have been collected at Government Wash and Lake Mohave as well as a third site near Cameron, Arizona. K, U, and Th concentrations of these samples have been determined using inductively coupled mass spectrometry (ICP-MS) and laboratory counting using radiation detection equipment. In addition, many sample locations also have

  8. 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

  9. Preparation of Reference Material 8504, Transformer Oil.

    PubMed

    Poster, Dianne L; Schantz, Michele M; Wise, Stephen A

    2005-01-01

    A new reference material (RM), RM 8504, has been prepared for use as a diluent oil with Aroclors in transformer oil Standard Reference Materials (SRMs) 3075 to 3080 and SRM 3090 when developing and validating methods for the determination of polychlorinated biphenyls (PCBs) as Aroclors in transformer oil or similar matrices. SRMs 3075-3080 and SRM 3090 consist of individual Aroclors in the same transformer oil that was used to prepare RM 8504. A unit of RM 8504 consists of one bottle containing approximately 100 mL of transformer oil. No additional constituents have been added to the oil.

  10. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Engineers which has been incorporated by reference. The first column lists the number and name of the... materials may be obtained from Society of Automotive Engineers International, 400 Commonwealth Dr..., Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations and Acronyms 90.114 SAE...

  11. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... forth material from the Society of Automotive Engineers which has been incorporated by reference. The... Automotive Engineers International, 400 Commonwealth Dr., Warrendale, PA 15096-0001. Document number and name... Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations and Acronyms 91.113. SAE...

  12. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... forth material from the Society of Automotive Engineers which has been incorporated by reference. The... Automotive Engineers International, 400 Commonwealth Dr., Warrendale, PA 15096-0001. Document number and name... Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations and Acronyms 91.113. SAE...

  13. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Engineers which has been incorporated by reference. The first column lists the number and name of the... materials may be obtained from Society of Automotive Engineers International, 400 Commonwealth Dr..., Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations and Acronyms 90.114 SAE...

  14. 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,…

  15. Development of synthetic environmental radioactivity reference materials.

    PubMed

    Harms, Arvic; Gilligan, Chris

    2012-09-01

    In this paper, a novel way of developing synthetic environmental radioactivity reference materials via the sol-gel process is described. Two solid reference materials (both having a SiO(2) matrix) were synthesised by hydrolysing a liquid mixture of tetraethyl orthosilicate (TEOS), ethanol and standardised mixed radionuclide solutions. The certified values, which were in the Bqg(-1) range, for the radionuclides in the material were determined by NPL and compared with results from measurements made by 36 organisations from 17 countries using a 'consensus' approach. The measurements were made within two wider test exercises (the NPL Environmental Radioactivity Proficiency Test Exercises 2009 and 2010). Certified activity concentration values were obtained for (60)Co, (133)Ba, (134)Cs, (137)Cs, (152)Eu, (154)Eu and (241)Am and indicative values were obtained for (55)Fe and (90)Sr.

  16. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Conformance with Specifications 91.207; 91.120; 91.509; 91.1307. (2) SAE material. The following table sets... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine and Systems-Power Measurements and Declarations 91.104, 91.115; 91.118; 91.207; 91.1307. SAE J1930 June...

  17. 40 CFR 91.6 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Conformance with Specifications 91.207; 91.120; 91.509; 91.1307. (2) SAE material. The following table sets... 40 CFR part 91 reference SAE J1228/ISO 8665 November 1991 Small Craft-Marine Propulsion Engine and Systems-Power Measurements and Declarations 91.104, 91.115; 91.118; 91.207; 91.1307. SAE J1930 June...

  18. Development of Argon Isotope Reference Standards for the U.S. Geological Survey

    PubMed Central

    Miiller, Archie P.

    2006-01-01

    The comparison of physical ages of geological materials measured by laboratories engaged in geochronological studies has been limited by the accuracy of mineral standards or monitors for which reported ages have differed by as much as 2 %. In order to address this problem, the U.S. Geological Survey is planning to calibrate the conventional 40Ar/40K age of a new preparation of an international hornblende standard labeled MMhb-2. The 40K concentration in MMhb-2 has already been determined by the Analytical Chemistry Division at NIST with an uncertainty of 0.2 %. The 40Ar concentration will be measured by the USGS using the argon isotope reference standards that were recently developed by NIST and are described in this paper. The isotope standards were constructed in the form of pipette/reservoir systems and calibrated by gas expansion techniques to deliver small high-precision aliquots of high-purity argon. Two of the pipette systems will deliver aliquots of 38Ar having initial molar quantities of 1.567 × 10−10 moles and 2.313 × 10−10 moles with expanded (k = 2) uncertainties of 0.058 % and 0.054 %, respectively. Three other pipette systems will deliver aliquots (nominally 4 × 10−10 moles) of 40Ar:36Ar artificial mixtures with similar accuracy and with molar ratios of 0.9974 ± 0.06 %, 29.69 ± 0.06 %, and 285.7 ± 0.08 % (k = 2). These isotope reference standards will enable the USGS to measure the 40Ar concentration in MMhb-2 with an expanded uncertainty of ≈ 0.1 %. In the process of these measurements, the USGS will re-determine the isotopic composition of atmospheric Ar and calculate a new value for its atomic weight. Upon completion of the USGS calibrations, the MMhb-2 mineral standard will be certified by NIST for its K and Ar concentrations and distributed as a Standard Reference Material (SRM). The new SRM and the NIST-calibrated transportable pipette systems have the potential for dramatically improving the accuracy of interlaboratory

  19. Development of Argon Isotope Reference Standards for the U.S. Geological Survey.

    PubMed

    Miiller, Archie P

    2006-01-01

    The comparison of physical ages of geological materials measured by laboratories engaged in geochronological studies has been limited by the accuracy of mineral standards or monitors for which reported ages have differed by as much as 2 %. In order to address this problem, the U.S. Geological Survey is planning to calibrate the conventional (40)Ar/(40)K age of a new preparation of an international hornblende standard labeled MMhb-2. The (40)K concentration in MMhb-2 has already been determined by the Analytical Chemistry Division at NIST with an uncertainty of 0.2 %. The (40)Ar concentration will be measured by the USGS using the argon isotope reference standards that were recently developed by NIST and are described in this paper. The isotope standards were constructed in the form of pipette/reservoir systems and calibrated by gas expansion techniques to deliver small high-precision aliquots of high-purity argon. Two of the pipette systems will deliver aliquots of (38)Ar having initial molar quantities of 1.567 × 10(-10) moles and 2.313 × 10(-10) moles with expanded (k = 2) uncertainties of 0.058 % and 0.054 %, respectively. Three other pipette systems will deliver aliquots (nominally 4 × 10(-10) moles) of (40)Ar:(36)Ar artificial mixtures with similar accuracy and with molar ratios of 0.9974 ± 0.06 %, 29.69 ± 0.06 %, and 285.7 ± 0.08 % (k = 2). These isotope reference standards will enable the USGS to measure the (40)Ar concentration in MMhb-2 with an expanded uncertainty of ≈ 0.1 %. In the process of these measurements, the USGS will re-determine the isotopic composition of atmospheric Ar and calculate a new value for its atomic weight. Upon completion of the USGS calibrations, the MMhb-2 mineral standard will be certified by NIST for its K and Ar concentrations and distributed as a Standard Reference Material (SRM). The new SRM and the NIST-calibrated transportable pipette systems have the potential for dramatically improving the accuracy of

  20. Demonstrating the comparability of certified reference materials.

    PubMed

    Duewer, David L; Lippa, Katrice A; Long, Stephen E; Murphy, Karen E; Sharpless, Katherine E; Sniegoski, Lorna T; Welch, Michael J; Tani, Wataru; Umemoto, Masao

    2009-09-01

    Certified reference materials (CRMs) enable the meaningful comparison of measurement results over time and place. When CRMs are used to calibrate or verify the performance of a measurement system, results produced by that system can be related through the CRM to well-defined, stable, and globally accessible reference(s). Properly done, this directly establishes the metrological traceability of the results. However, achieving the meaningful comparison of results from measurement systems calibrated and/or verified with different CRMs requires that the different materials truly deliver the same measurand, that is, are "the same" within stated uncertainty except for differences in the level of the analyte of interest. We here detail experimental and data analysis techniques for establishing and demonstrating the comparability of materials. We focus on (1) establishing a uniform interpretation of the common forms of CRM uncertainty statements, (2) estimating consistent measurement system response uncertainties from sometimes inconsistent experimental designs, (3) using "errors-in-variables" analysis methods to evaluate comparability studies and novel graphical tools for communicating results of the evaluation to reviewing authorities and potential CRM customers, and (4) augmenting established comparability studies with new materials using measurements provided by the certifying institution. These experimental and data analytic tools were developed in support of the Joint Committee for Traceability in Laboratory Medicine's efforts to enhance the reliability of clinical laboratory measurements and are illustrated with potassium and cholesterol measurands of clinical relevance; however, these tools can be applied to any group of materials that deliver the same nominal measurand with stated value and uncertainty.

  1. Analysis of naturally produced technetium and plutonium in geologic materials.

    PubMed

    Dixon, P; Curtis, D B; Musgrave, J; Roensch, F; Roach, J; Rokop, D

    1997-05-01

    In uncontaminated natural materials, plutonium and technetium exist exclusively as products (daughters) of nuclear reactions in which uranium is the principal reactant (parent). Under conditions of chemical stability over geologic periods of time, the relative abundances of daughter and parent elements are fixed by the rates of nuclear reactions and the decay of the daughter radionuclide. The state of this nuclear secular equilibrium condition is the primary basis of the geochemical study of these elements in nature. Thus, it is critical that nuclear parent and daughter abundances are measured in the same sample. We have developed a quantitative procedure for measuring subpicogram quantities of plutonium and technetium in gram quantities of geologic matrices such as uranium ores. The procedure takes advantage of the aggressive properties of sodium peroxide/hydroxide fusion to ensure complete dissolution and homogenization of complex materials, the precision provided by isotope dilution techniques, and the extreme sensitivity offered by thermal ionization mass spectrometry. Using this technique, a quantitative aliquot can be removed for uranium analysis by isotope dilution thermal ionization mass spectrometry or α spectrometry. Although the application of the procedure is unique, the analytical concepts may find more general application in studies of environmental contamination by nuclear materials. To assess the precision and accuracy of the analytical results, blanks and standards were analyzed routinely for a 1-year period to ensure quality control of our sample analyses. The average technetium blank is 5 ± 4 fg (n = 8), and that for plutonium is 0.17 ± 0.15 pg (n = 7). Thus, the detection limit for technetium (defined as 3 times the standard deviation of the average blank) is 11 fg, and that for plutonium is 0.44 pg. To assess the procedural precision, Canadian Reference Material BL-5 was analyzed routinely with samples. The results of seven replicate

  2. Geological and geochemical aspects of uranium deposits: a selected, annotated bibliography. [474 references

    SciTech Connect

    Thomas, J.M.; Garland, P.A.; White, M.B.; Daniel, E.W.

    1980-09-01

    This bibliography, a compilation of 474 references, is the fourth in a series compiled from the National Uranium Resource Evaluation (NURE) Bibliographic Data Base. This data base was created for the Grand Junction Office of the Department of Energy's National Uranium Resource Evaluation Project by the Ecological Sciences Information Center, Oak Ridge National Laboratory. The references in the bibliography are arranged by subject category: (1) geochemistry, (2) exploration, (3) mineralogy, (4) genesis of deposits, (5) geology of deposits, (6) uranium industry, (7) geology of potential uranium-bearing areas, and (8) reserves and resources. The references are indexed by author, geographic location, quadrangle name, geoformational feature, and keyword.

  3. Dynamic High-Pressure Behavior of Hierarchical Heterogeneous Geological Materials

    DTIC Science & Technology

    2016-04-01

    inherent in the case of geological or earth materials (such as rocks and soil), as well as structurally-engineered or synthetic monolithic and composite...materials including soils and rocks are examples of heterogeneous materials containing discrete heterogeneities of vastly different impedances. The...inelastic loading cycles . The difference between the two could be attributed to the large amounts of zero strength material in ‘mix 3’ simulations that

  4. Micromechanical Behavior of Frictional Geologic Materials

    DTIC Science & Technology

    1988-11-01

    ranging from a suspension of particles to multicontacted particles forming a material with continuous force-deformation characteristics, i.e., a...Vol. 14, No. 4, pp. 25-38 (1974). 15. Biarez, J., "Contribution a l’Etude des Proprietes Mecaniques des Sols et des Materiaux Pulverulents," These de

  5. 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).

  6. Thermal Diffusivity of Carbon Materials as Candidate Reference Materials

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

    Thermal-diffusivity measurements using the laser-flash method have been investigated in order to establish a thermal diffusivity standard. In many cases, thermal-conductivity values of bulk materials are calculated from the thermal diffusivity, specific heat capacity, and bulk density. The thermal diffusivity is one of the transport properties. It depends on the material and is sensitive to the structure. So, it is important to measure the thermal diffusivity of each material. The laser-flash method is one of the most popular methods for thermal-diffusivity measurements of bulk materials above room temperature. Because the method realizes a short-time method and is a non-contact method, it is very suitable for practical use. And it is known as a highly reliable measurement since one-dimensional heat diffusion phenomena observed in these measurements are simple. On the other hand, more reliable values measured by the method are important in the view of thermal design. According to the background, there is a need of a standard for thermal-diffusivity measurements using the laser-flash method to obtain reliable thermal diffusivities. The National Metrology Institute of Japan (NMIJ) in AIST has established reference materials for the laser-flash method and is supplying them. However, they are not sufficient to cover the whole range of thermal-diffusivity measurements. Thus, some candidate materials have been investigated to establish another reference material. Carbon materials are considered since it is preferable for the laser-flash method that the material is optically nontransparent and dark colored (ideally black). In this study, the thermal diffusivity of a pyrolytic graphite that is expected to be a candidate reference material for the laser-flash method is investigated. It was found that the intrinsic thermal diffusivities can be determined along the in-plane and cross-plane directions. The high thermal diffusivity of the in-plane direction, 1.19 × 10^{-3} m2

  7. 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.

  8. Determination of carbonate carbon in geological materials by coulometric titration

    USGS Publications Warehouse

    Engleman, E.E.; Jackson, L.L.; Norton, D.R.

    1985-01-01

    A coulometric titration is used for the determination of carbonate carbon in geological materials. Carbon dioxide is evolved from the sample by the addition of 2 M perchloric acid, with heating, and is determined by automated coulometric titration. The coulometric titration showed improved speed and precision with comparable accuracy to gravimetric and gasometric techniques. ?? 1985.

  9. 40 CFR 90.7 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (1) ASTM material. The following table sets forth material from the American Society for Testing and... materials may be obtained from American Society for Testing and Materials, 1916 Race St., Philadelphia, PA....116; 90.509. (2) SAE material. The following table sets forth material from the Society of...

  10. Re-evaluation and extension of the scope of elements in US Geological Survey Standard Reference Water Samples

    USGS Publications Warehouse

    Peart, D.B.; Antweiler, R.C.; Taylor, H.E.; Roth, D.A.; Brinton, T.I.

    1998-01-01

    More than 100 US Geological Survey (USGS) Standard Reference Water Samples (SRWSs) were analyzed for numerous trace constituents, including Al, As, B, Ba, Be, Bi, Br, Cd, Cr, Co, Cu, I, Fe, Pb, Li, Mn, Mo, Ni, Rb, Sb, Se, Sr, Te, Tl, U, V, Zn and major elements (Ca, Mg, Na, SiO2, SO4, Cl) by inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectrometry. In addition, 15 USGS SRWSs and National Institute of Standards and Technology (NIST) standard reference material (SRM) 1641b were analyzed for mercury using cold vapor atomic fluorescence spectrometry. Also USGS SRWS Hg-7 was analyzed using isotope dilution-inductively coupled plasma mass spectrometry. The results were compared with the reported certified values of the following standard reference materials: NIST SRM 1643a, 1643b, 1643c and 1643d and National Research Council of Canada Riverine Water Reference Materials for Trace Metals SLRS-1, SLRS-2 and SLRS-3. New concentration values for trace and major elements in the SRWSs, traceable to the certified standards, are reported. Additional concentration values are reported for elements that were neither previously published for the SRWSs nor traceable to the certified reference materials. Robust statistical procedures were used that were insensitive to outliers. These data can be used for quality assurance/quality control purposes in analytical laboratories.

  11. Electrostatic aggregation of finely-comminuted geological materials

    NASA Technical Reports Server (NTRS)

    Marshall, J. R.; Greeley, R.

    1986-01-01

    Electrostatic forces are known to have a significant effect on the behavior of finely comminuted particulate material: perhaps the most prevalent expression of this being electrostatic aggregation of particles into relatively coherent clumps. However, the precise role of electrostatic attraction and repulsion in determining the behavior of geological materials (such as volcanic ash and aeolian dust) is poorly understood. Electrostatic aggregation of fine particles is difficult to study on Earth either in the geological or laboratory environment principally because the material in an aggregated state remains airborne for such a short period of time. Experiments conducted in the NASA/JCS - KC135 aircraft are discussed. The aircraft experiments are seen as precursors to more elaborate and scientifically more comprehensive Shuttle or Space Station activities.

  12. Electrostatic aggregation of finely-comminuted geological materials

    NASA Technical Reports Server (NTRS)

    Marshall, John R.; Greeley, Ronald

    1987-01-01

    Electrostatic forces are known to have a significant effect on the behavior of finely comminuted particulate material: perhaps the most prevalent expression of this being electrostatic aggregation of particles into relatively coherent clumps. However, the precise role of electrostatic attraction and repulsion in determining the behavior of geological materials (such as volcanic ash and aeolian dust) is poorly understood. Electrostatic aggregation of fine particles is difficult to study on earth either in the geological or laboratory environment principally because the material in an aggregated state remains airborne for such a short period of time. Experiments conducted in the NASA/JSC - KC135 aircraft are discussed. The aircraft experiments are seen as precursors to more elaborate and scientifically more comprehensive Shuttle or Space Station activities.

  13. Biological reference materials for extracellular vesicle studies.

    PubMed

    Valkonen, S; van der Pol, E; Böing, A; Yuana, Y; Yliperttula, M; Nieuwland, R; Laitinen, S; Siljander, P R M

    2017-02-15

    Extracellular vesicles (EVs) mediate normal physiological homeostasis and pathological processes by facilitating intercellular communication. Research of EVs in basic science and clinical settings requires both methodological standardization and development of reference materials (RM). Here, we show insights and results of biological RM development for EV studies. We used a three-step approach to find and develop a biological RM. First, a literature search was done to find candidates for biological RMs. Second, a questionnaire was sent to EV researchers querying the preferences for RM and their use. Third, a biological RM was selected, developed, characterized, and evaluated. The responses to the survey demonstrated a clear and recognized need for RM optimized for the calibration of EV measurements. Based on the literature, naturally occurring and produced biological RM, such as virus particles and liposomes, were proposed as RM. However, none of these candidate RMs have properties completely matching those of EVs, such as size and refractive index distribution. Therefore, we evaluated the use of nanoerythrosomes (NanoE), vesicles produced from erythrocytes, as a potential biological RM. The strength of NanoE is their resemblance to EVs. Compared to the erythrocyte-derived EVs (eryEVs), NanoE have similar morphology, a similar refractive index (1.37), larger diameter (70% of the NanoE are over 200nm), and increased positive staining for CD235a and lipids (Di-8-ANEPPS) (58% and 67% in NanoE vs. 21% and 45% in eryEVs, respectively). Altogether, our results highlight the general need to develop and validate new RM with similar physical and biochemical properties as EVs to standardize EV measurements between instruments and laboratories.

  14. Engineering considerations for the recovery of cesium from geologic materials

    SciTech Connect

    Whalen, C.

    1993-05-18

    Sorption coefficients for cesium in a variety of media have been compiled from a search of the open literature. The sorption coefficient, or K{sub d}, is a description of a dissolved substance`s tendency to attach to a solid substrate. The compilation of K{sub d}S reported here for cesium demonstrate that this element readily sorbs onto-geological material. As a result of this sorption, the mass transport of cesium in the environment will be retarded. This retarded mass transport, characterized by the retardation factor, can be expected to be significant when compared to water velocities through porous-sorbing medium, such as geologic materials. K{sub d}S for cesium are in the range of 100 m{ell}/g up to 10,000 m{ell}/g. K{sub d}S are also an important parameter in the design of engineered systems for the purpose of recovering cesium from soils. The engineering design is based on a material-balance description of the extraction process. The information presented in this report provides a basis to predict the movement of cesium through geologic materials and also to design and predict the performance of extraction processes such as soil washing.

  15. Engineering considerations for the recovery of cesium from geologic materials

    SciTech Connect

    Whalen, C.

    1993-05-18

    Sorption coefficients for cesium in a variety of media have been compiled from a search of the open literature. The sorption coefficient, or K[sub d], is a description of a dissolved substance's tendency to attach to a solid substrate. The compilation of K[sub d]S reported here for cesium demonstrate that this element readily sorbs onto-geological material. As a result of this sorption, the mass transport of cesium in the environment will be retarded. This retarded mass transport, characterized by the retardation factor, can be expected to be significant when compared to water velocities through porous-sorbing medium, such as geologic materials. K[sub d]S for cesium are in the range of 100 m[ell]/g up to 10,000 m[ell]/g. K[sub d]S are also an important parameter in the design of engineered systems for the purpose of recovering cesium from soils. The engineering design is based on a material-balance description of the extraction process. The information presented in this report provides a basis to predict the movement of cesium through geologic materials and also to design and predict the performance of extraction processes such as soil washing.

  16. Single And Multiple Jet Penetration Experiments Into Geologic Materials

    SciTech Connect

    Kuklo, R; Murphy, M J; Rambur, T A; Switzer, L L; Summers, M A

    2003-12-19

    This paper presents the results of experiments that investigate the effect of single and multiple jet penetration into geologic materials. In previous studies of jet penetration into concrete targets, we demonstrated that an enhanced surface crater could be created by the simultaneous penetration of multiple shaped charge jets and that an enhanced target borehole could be created by the subsequent delayed penetration of a single shaped charge jet. This paper describes an extension of the multiple jet penetration research to limestone and granite.

  17. 40 CFR 194.13 - Submission of reference materials.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Santa Fe, New Mexico. Reference materials that are widely available in standard text books or reference books need not to be submitted. Whenever possible, DOE shall submit 10 copies of reference materials in alternative format (e.g., compact disk) or other approved format, as specified by...

  18. 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... Federal Register and the material must be available to the public. All approved material is available...

  19. 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

  20. 15 CFR 200.104 - Standard reference materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the NIST National Measurement Laboratory administers a program to provide many types of well... be readily referred to a common base. NIST SP 260 is a catalog of Standard Reference Materials available from NIST....

  1. 15 CFR 200.104 - Standard reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the NIST National Measurement Laboratory administers a program to provide many types of well... be readily referred to a common base. NIST SP 260 is a catalog of Standard Reference Materials available from NIST....

  2. 15 CFR 200.104 - Standard reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the NIST National Measurement Laboratory administers a program to provide many types of well... be readily referred to a common base. NIST SP 260 is a catalog of Standard Reference Materials available from NIST....

  3. 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.

  4. 40 CFR 94.5 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... lists material from the International Organization for Standardization that we have incorporated by... International Organization for Standardization, Case Postale 56, CH-1211 Geneva 20, Switzerland. Table 2...

  5. Predictive Modeling of Terrestrial Radiation Exposure from Geologic Materials

    SciTech Connect

    Malchow, Russell L.; Haber, Daniel University of Nevada, Las Vegas; Burnley, Pamela; Marsac, Kara; Hausrath, Elisabeth; Adcock, Christopher

    2015-01-01

    Aerial gamma ray surveys are important for those working in nuclear security and industry for determining locations of both anthropogenic radiological sources and natural occurrences of radionuclides. During an aerial gamma ray survey, a low flying aircraft, such as a helicopter, flies in a linear pattern across the survey area while measuring the gamma emissions with a sodium iodide (NaI) detector. Currently, if a gamma ray survey is being flown in an area, the only way to correct for geologic sources of gamma rays is to have flown the area previously. This is prohibitively expensive and would require complete national coverage. This project’s goal is to model the geologic contribution to radiological backgrounds using published geochemical data, GIS software, remote sensing, calculations, and modeling software. K, U and Th are the three major gamma emitters in geologic material. U and Th are assumed to be in secular equilibrium with their daughter isotopes. If K, U, and Th abundance values are known for a given geologic unit the expected gamma ray exposure rate can be calculated using the Grasty equation or by modeling software. Monte Carlo N-Particle Transport software (MCNP), developed by Los Alamos National Laboratory, is modeling software designed to simulate particles and their interactions with matter. Using this software, models have been created that represent various lithologies. These simulations randomly generate gamma ray photons at energy levels expected from natural radiologic sources. The photons take a random path through the simulated geologic media and deposit their energy at the end of their track. A series of nested spheres have been created and filled with simulated atmosphere to record energy deposition. Energies deposited are binned in the same manner as the NaI detectors used during an aerial survey. These models are used in place of the simplistic Grasty equation as they take into account absorption properties of the lithology which the

  6. 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.

  7. 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)

  8. 40 CFR 1042.910 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL OF EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Definitions and.../federal_register/code_of_federal_regulations/ibr_locations.html. (a) IMO material. This paragraph...

  9. 40 CFR 1043.100 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL OF NOX, SOX, AND PM EMISSIONS FROM MARINE ENGINES AND VESSELS SUBJECT TO THE MARPOL PROTOCOL.../federal_register/code_of_federal_regulations/ibr_locations.html. (a) IMO material. This paragraph...

  10. 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.

  11. Determination of carbon-14 in environmental level, solid reference materials.

    PubMed

    Blowers, Paul; Caborn, Jane; Dell, Tony; Gingell, Terry; Harms, Arvic; Long, Stephanie; Sleep, Darren; Stewart, Charlie; Walker, Jill; Warwick, Phil E

    2011-10-01

    An intercomparison exercise to determine the (14)C activity concentrations in a range of solid, environmental level materials was conducted between laboratories in the UK. IAEA reference materials, C2, C6 and C7, and an in-house laboratory QA material were dispatched in 2006 to ten laboratories comprising of members of the Analyst Informal Working Group (AIWG) and one other invited party. The laboratories performed the determinations using a number of techniques, and using the results each one was evaluated in terms of levels of precision, sensitivity and limits of detection. The results of the study show that all techniques are capable of successfully analysing (14)C in environmental level materials, however, a shortage of certified environmental reference materials exists. The suitability of the IAEA reference materials and other material for use as reference materials was also assessed.

  12. 40 CFR 86.1 - Reference materials.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... for Determination of Solar Reflectance Near Ambient Temperature Using a Portable Solar Reflectometer...) ASTM E903-96, Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials..., Standard Test Method for Measuring Solar Reflectance of Horizontal and Low-Sloped Surfaces in the...

  13. The sorption of polonium, actinium and protactinium onto geological materials

    SciTech Connect

    Baston, G.M.N.; Berry, J.A.; Brownsword, M.; Heath, T.G.; Ilett, D.J.; McCrohon, R.; Tweed, C.J.; Yui, M.

    1999-07-01

    This paper describes a combined experimental and modeling program of generic sorption studies to increase confidence in the performance assessment for a potential high-level radioactive waste repository in Japan. The sorption of polonium, actinium and protactinium onto geological materials has been investigated. Sorption of these radioelements onto bentonite, tuff and granodiorite from equilibrated de-ionized water was studied under reducing conditions at room temperature. In addition, the sorption of actinium and protactinium was investigated at 60 C. Thermodynamic chemical modeling was carried out to aid interpretation of the results.

  14. USE OF NATURAL WATERS AS U. S. GEOLOGICAL SURVEY REFERENCE SAMPLES.

    USGS Publications Warehouse

    Janzer, Victor J.

    1985-01-01

    The U. S. Geological Survey conducts research and collects hydrologic data relating to the Nation's water resources. Seven types of natural matrix reference water samples are prepared for use in the Survey's quality assurance program. These include samples containing major constituents, trace metals, nutrients, herbicides, insecticides, trace metals in a water and suspended-sediment mixture, and precipitation (snowmelt). To prepare these reference samples, natural water is collected in plastic drums and the sediment is allowed to settle. The water is then filtered, selected constituents are added, and if necessary the water is acidified and sterilized by ultraviolet irradiation before bottling in plastic or glass. These reference samples are distributed twice yearly to more than 100 laboratories for chemical analysis. The most probable values for each constituent are determined by evaluating the data submitted by the laboratories using statistical techniques recommended by ASTM.

  15. 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.

  16. 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.

  17. Reference Materials and Reference Measurement Procedures: An Overview from a National Metrology Institute

    PubMed Central

    Bunk, David M

    2007-01-01

    An outline of the processes involved in both certified clinical reference material production and clinical reference measurement procedure development at the National Institute of Standards and Technology (NIST), the national metrology institute of the United States, is presented. The role that NIST and other national metrology institutes play in the metrological traceability of certified reference material is discussed. Highlighted are the challenges associated with the development of reference measurement systems for complex clinical analytes, such as proteins, and examples of existing efforts in this area are given. Examples of recent international collaborations in developing certified reference materials for analytes such as cardiac troponin I, brain natriuretic peptide, and serum creatinine demonstrate the close cooperation that national metrology institutes must have with the clinical community to establish complete reference measurement systems. PMID:18392127

  18. U.S. Geological Survey Standard Reference Sample Project: Performance Evaluation of Analytical Laboratories

    USGS Publications Warehouse

    Long, H. Keith; Daddow, Richard L.; Farrar, Jerry W.

    1998-01-01

    Since 1962, the U.S. Geological Survey (USGS) has operated the Standard Reference Sample Project to evaluate the performance of USGS, cooperator, and contractor analytical laboratories that analyze chemical constituents of environmental samples. The laboratories are evaluated by using performance evaluation samples, called Standard Reference Samples (SRSs). SRSs are submitted to laboratories semi-annually for round-robin laboratory performance comparison purposes. Currently, approximately 100 laboratories are evaluated for their analytical performance on six SRSs for inorganic and nutrient constituents. As part of the SRS Project, a surplus of homogeneous, stable SRSs is maintained for purchase by USGS offices and participating laboratories for use in continuing quality-assurance and quality-control activities. Statistical evaluation of the laboratories results provides information to compare the analytical performance of the laboratories and to determine possible analytical deficiences and problems. SRS results also provide information on the bias and variability of different analytical methods used in the SRS analyses.

  19. 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

  20. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Impact Hybrid Dummy 50th Percentile Male § 572.110 Materials incorporated by reference. (a) The following..., SID/Hybrid III part 572, subpart M, dated May 10, 1997. (2) The SID/Hybrid III Part 572 Subpart M...

  1. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Impact Hybrid Dummy 50th Percentile Male § 572.110 Materials incorporated by reference. (a) The following..., SID/Hybrid III part 572, subpart M, dated May 10, 1997. (2) The SID/Hybrid III Part 572 Subpart M...

  2. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 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 the... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.223 Section...

  3. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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 the... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.223 Section...

  4. 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

  5. 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

  6. Instructional Materials in the Classroom; A Basic Reference Shelf.

    ERIC Educational Resources Information Center

    Stanford Univ., CA. ERIC Clearinghouse on Educational Media and Technology.

    In an attempt to pull together a basic reference shelf on the use of instructional materials in the classroom, this bibliography contains 69 selected ERIC abstracts of the most relevant and up-to-date indexes, resource guides, directories, "how-to's", and state-of-the-art reviews dealing with the use of audiovisual materials in education. Selected…

  7. 14 CFR 171.71 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Headquarters. An historical file of these materials is maintained at Headquarters, Federal Aviation... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 171.71 Section 171.71 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF...

  8. Building a geological reference platform using sequence stratigraphy combined with geostatistical tools

    NASA Astrophysics Data System (ADS)

    Bourgine, Bernard; Lasseur, Éric; Leynet, Aurélien; Badinier, Guillaume; Ortega, Carole; Issautier, Benoit; Bouchet, Valentin

    2015-04-01

    In 2012 BRGM launched an extensive program to build the new French Geological Reference platform (RGF). Among the objectives of this program is to provide the public with validated, reliable and 3D-consistent geological data, with estimation of uncertainty. Approx. 100,000 boreholes over the whole French national territory provide a preliminary interpretation in terms of depths of main geological interfaces, but with an unchecked, unknown and often low reliability. The aim of this paper is to present the procedure that has been tested on two areas in France, in order to validate (or not) these boreholes, with the aim of being generalized as much as possible to the nearly 100,000 boreholes waiting for validation. The approach is based on the following steps, and includes the management of uncertainty at different steps: (a) Selection of a loose network of boreholes owning a logging or coring information enabling a reliable interpretation. This first interpretation is based on the correlation of well log data and allows defining 3D sequence stratigraphic framework identifying isochronous surfaces. A litho-stratigraphic interpretation is also performed. Be "A" the collection of all boreholes used for this step (typically 3 % of the total number of holes to be validated) and "B" the other boreholes to validate, (b) Geostatistical analysis of characteristic geological interfaces. The analysis is carried out firstly on the "A" type data (to validate the variogram model), then on the "B" type data and at last on "B" knowing "A". It is based on cross-validation tests and evaluation of the uncertainty associated to each geological interface. In this step, we take into account inequality constraints provided by boreholes that do not intersect all interfaces, as well as the "litho-stratigraphic pile" defining the formations and their relationships (depositing surfaces or erosion). The goal is to identify quickly and semi-automatically potential errors among the data, up to

  9. Genetic reference materials and their application to haematology.

    PubMed

    Hawkins, J R; Hawkins, M; Boyle, J; Gray, E; Matejtschuk, P; Metcalfe, P

    2010-07-01

    Genetic investigations are becoming increasingly useful and widespread in many areas of human health. However, there is a worldwide lack of certified reference materials for use in genetic testing, meaning that tests are being run without well validated controls and new assays are more difficult to develop and validate. We have responded to this challenge by starting a programme of developing genetic reference materials (GRMs) for international accreditation and worldwide distribution. Our approach has been to make materials for disorders where testing is commonplace and genotyping errors have been demonstrated. To ensure a continuing supply of DNA, cell lines are established from consenting, phenotypically well-characterised patients and are then grown up in bulk for genomic DNA extraction to yield up to 100 milligrams of DNA. In most cases the DNA is then formulated, freeze-dried and sealed in glass ampoules to ensure greater stability over time and obviate the need for chilled transportation. In this paper we explore the options and routes available to the production of DNA reference materials and describe the establishment of the first internationally recognised reference materials for human genomic DNA, with particular reference to some genetic tests carried out frequently within haematological and cardiovascular laboratories.

  10. Development of reference conditions for geologic repositories for nuclear waste in the USA

    NASA Astrophysics Data System (ADS)

    Raines, G. E.; Rickertsen, L. D.; Claiborne, H. C.; McElroy, J. L.; Lynch, R. W.

    1980-10-01

    Activities are described which determine interim reference conditions for temperatures, pressure, fluid, chemical, and radiation environments that are expected to exist in commercial and defense high level nuclear waste and spent fuel repositories in salt, basalt, tuff, granite and shale. The reference repository conditions developed are intended to serve as a guide for: (1) scientists conducting material performance tests; (2) engineers preparing the design of repositories; (3) the technically conservative conditions to be used as a basis for DOE license applications; and (4) scientists and engineers developing waste forms.

  11. Digestion of titanium bearing geologic materials involving microwaves.

    PubMed

    Tripathi, Anju; Chattopadhyay, Partha

    2007-10-01

    An environmentally friendly and rapid digestion procedure involving 10 mL of acid mixture (HNO3 : HCl : HF = 2:2:1) for 0.1 g of sample in closed vessel microwave digester following heating program : 250W for 10 min., hold time 2 min., 600 W for 17 min, and Ventilation time 10 min was developed. The operating parameters were varied and optimized by factorial design approach using "Steepest Ascent" method. The validity of the recommended digestion procedure were examined by analyzing several well characterized standard reference materials such as diabase (W2), basalt (BIR-1, JB-3, BHVO-1), granite (G2), gabbro (JGb-1), Mn-nodule (Nod-A-1, Nod-P-1), sediment (STSD-4, LKSD-2), limestone (KH-2), soil (SAu-1), ilmenite (IGS-31), rutile (IGS-32), Zircon (IGS-35) and titanium dioxide (SRM-154b) employing both inductively coupled plasma-atomic emission spectrometry (ICP-AES) and well known spectrophotometric method. An excellent agreement between the methods and the certified values of standard reference materials suggest that the digestion procedure can be used for quality control and allied purposes.

  12. Reference materials and reference measurement systems in laboratory medicine. Harmonization of nomenclature and definitions in reference measurement systems.

    PubMed

    Dybkaer, R

    1995-12-01

    Reliability of clinical laboratory results is obtained through quality assurance in both their production and transmission. The former involves a reference measurement system of reference materials and reference measurement procedures with metrological and statistical verification of results. The latter requires that sender and receiver have access to a common terminology. Thus, two data banks are required. A plurilingual systematic vocabulary related to the reference measurement system, giving concepts with terms and definitions concerning measurement standards, reference measurement procedures, internal quality control, external quality assessment, probability and statistics-mainly based on existing authoritative publications. The material should be processed by standard scientific terminological procedure and offered to pertinent organizations and specialists for comment before finalization and authorization. A multilingual collection of systematic names for properties examined by the branches of Laboratory Medicine, such as clinical chemistry, clinical immunology, clinical microbiology, clinical pharmacology, haematology and blood banking, and histochemistry and cytology. The database should function as a reference to consultation and as a link in the transmission of data between local laboratory "dialects". This should be based on the ongoing comprehensive IUPAC/IFCC project for forming names in collaboration with relevant scientific organisations and area specialists. The relational data base including "run-time" software would be accessed by e-mail (gopher or other storage medium).

  13. [The water content reference material of water saturated octanol].

    PubMed

    Wang, Haifeng; Ma, Kang; Zhang, Wei; Li, Zhanyuan

    2011-03-01

    The national standards of biofuels specify the technique specification and analytical methods. A water content certified reference material based on the water saturated octanol was developed in order to satisfy the needs of the instrument calibration and the methods validation, assure the accuracy and consistency of results in water content measurements of biofuels. Three analytical methods based on different theories were employed to certify the water content of the reference material, including Karl Fischer coulometric titration, Karl Fischer volumetric titration and quantitative nuclear magnetic resonance. The consistency of coulometric and volumetric titration was achieved through the improvement of methods. The accuracy of the certified result was improved by the introduction of the new method of quantitative nuclear magnetic resonance. Finally, the certified value of reference material is 4.76% with an expanded uncertainty of 0.09%.

  14. The use of reference materials in isotope measurements (Invited)

    NASA Astrophysics Data System (ADS)

    Kessel, R.

    2009-12-01

    Over the last few decades, mass spectrometry has emerged as one of the most important tools for chemical analysis. Isotope measurements on modern mass spectrometers have achieved unprecedented repeatability due to the semi-automated nature and stability. As a consequence of these high precisions, one of the most important factors for improving the total uncertainty of the measurement results is associated with the reference materials used for calibration. Different metrological concepts have been developed to deal with this problem. This talk will examine the impact of these concepts involving reference materials on the uncertainty budget, traceability and comparability of the results.

  15. 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.

  16. 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.

  17. 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.

  18. Geology

    NASA Technical Reports Server (NTRS)

    Stewart, R. K.; Sabins, F. F., Jr.; Rowan, L. C.; Short, N. M.

    1975-01-01

    Papers from private industry reporting applications of remote sensing to oil and gas exploration were presented. Digitally processed LANDSAT images were successfully employed in several geologic interpretations. A growing interest in digital image processing among the geologic user community was shown. The papers covered a wide geographic range and a wide technical and application range. Topics included: (1) oil and gas exploration, by use of radar and multisensor studies as well as by use of LANDSAT imagery or LANDSAT digital data, (2) mineral exploration, by mapping from LANDSAT and Skylab imagery and by LANDSAT digital processing, (3) geothermal energy studies with Skylab imagery, (4) environmental and engineering geology, by use of radar or LANDSAT and Skylab imagery, (5) regional mapping and interpretation, and digital and spectral methods.

  19. 10 CFR 433.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, Sixth... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.3 Materials incorporated by reference....

  20. 10 CFR 431.263 - 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. 431.263 Section 431.263 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL..., Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies Program), 1000...

  1. 10 CFR 433.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, Sixth... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.3 Materials incorporated by reference....

  2. 10 CFR 433.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, Sixth... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY STANDARDS FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.3 Materials incorporated by reference....

  3. 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..., Forrestal Building, Room 1J-018 (Resource Room of the Building Technologies Program), 1000...

  4. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Society of Automotive Engineers (SAE) J1733 Information Report, titled “Sign Convention for Vehicle Crash Testing,” dated December 1994. (16) SAE Recommended Practice J211, “Instrumentation for Impact Tests...) The SAE materials referred to in paragraphs (a)(15) and (a)(16) of this section are available from...

  5. 49 CFR 572.110 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Society of Automotive Engineers (SAE) J1733 Information Report, titled “Sign Convention for Vehicle Crash Testing,” dated December 1994. (16) SAE Recommended Practice J211, “Instrumentation for Impact Tests...) The SAE materials referred to in paragraphs (a)(15) and (a)(16) of this section are available from...

  6. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine Tuberculosis Eradication. The Uniform Methods and Rules—Bovine Tuberculosis Eradication (January 22, 1999, edition)...

  7. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine Tuberculosis Eradication. The Uniform Methods and Rules—Bovine Tuberculosis Eradication (January 22, 1999, edition)...

  8. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine Tuberculosis Eradication. The Uniform Methods and Rules—Bovine Tuberculosis Eradication (January 22, 1999, edition)...

  9. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine Tuberculosis Eradication. The Uniform Methods and Rules—Bovine Tuberculosis Eradication (January 22, 1999, edition)...

  10. 9 CFR 77.1 - Material incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS TUBERCULOSIS General Provisions § 77.1 Material incorporated by reference. Uniform Methods and Rules—Bovine Tuberculosis Eradication. The Uniform Methods and Rules—Bovine Tuberculosis Eradication (January 22, 1999, edition)...

  11. 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...

  12. 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...

  13. 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...

  14. 10 CFR 431.85 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza, SW... 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 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..._regulations/ibr_locations.html. (ii) U.S. Department of Energy, Office of Energy Efficiency and Renewable... 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...

  16. 10 CFR 431.323 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.323 Section 431.323 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  17. 10 CFR 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..._regulations/ibr_locations.html. (ii) U.S. Department of Energy, Office of Energy Efficiency and Renewable... 10 Energy 3 2010-01-01 2010-01-01 false Materials incorporated by reference. 431.105 Section 431.105 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  18. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Energy Efficiency and Renewable Energy, Hearings and Dockets, “Test Procedures and Efficiency Standards... 10 Energy 3 2012-01-01 2012-01-01 false Materials incorporated by reference. 431.95 Section 431.95 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...

  19. 10 CFR 431.85 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza, SW... 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...

  20. 10 CFR 431.105 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant... 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...

  1. 10 CFR 431.133 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... inspection at the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.133 Section 431.133 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  2. 10 CFR 431.293 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... 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...

  3. 10 CFR 431.263 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza SW... 10 Energy 3 2014-01-01 2014-01-01 false Materials incorporated by reference. 431.263 Section 431.263 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN...

  4. 10 CFR 431.293 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th... 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...

  5. 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.

  6. Determination of the rare-earth elements in geological materials by inductively coupled plasma mass spectrometry

    USGS Publications Warehouse

    Lichte, F.E.; Meier, A.L.; Crock, J.G.

    1987-01-01

    A method of analysis of geological materials for the determination of the rare-earth elements using the Inductively coupled plasma mass spectrometric technique (ICP-MS) has been developed. Instrumental parameters and factors affecting analytical results have been first studied and then optimized. Samples are analyzed directly following an acid digestion, without the need for separation or preconcentration with limits of detection of 2-11 ng/g, precision of ?? 2.5% relative standard deviation, and accuracy comparable to inductively coupled plasma emission spectrometry and instrumental neutron activation analysis. A commercially available ICP-MS instrument is used with modifications to the sample introduction system, torch, and sampler orifice to reduce the effects of high salt content of sample solutions prepared from geologic materials. Corrections for isobaric interferences from oxide ions and other diatomic and triatomic ions are made mathematically. Special internal standard procedures are used to compensate for drift in metahmetal oxide ratios and sensitivity. Reference standard values are used to verify the accuracy and utility of the method.

  7. 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

  8. Emission spectrographic determination of volatile trace elements in geologic materials by a carrier distillation technique

    USGS Publications Warehouse

    Barton, H.N.

    1986-01-01

    Trace levels of chalcophile elements that form volatile sulfide minerals are determined in stream sediments and in the nonmagnetic fraction of a heavy-mineral concentrate of stream sediments by a carrier distillation emission spectrographic method. Photographically recorded spectra of samples are visually compared with those of synthetic standards for the two sample types. Rock and soil samples may also be analyzed by comparison with the stream-sediment standards. A gallium oxide spectrochemical carrier/buffer enhances the early emission of the volatile elements. Detection limits in parts per million attained are: Sb 5, As 20, Bi 0.1, Cd 1, Cu 1, Pb 2, Ag 0.1, Zn 2, and Sn 0.1. A comparison with other methods of analysis, total-burn emission and atomic absorption spectroscopy, shows good correlation for standard reference for materials and samples from a variety of geologic terranes. ?? 1986.

  9. 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.

  10. Water as a source of errors in reference materials.

    PubMed

    Rückold, S; Grobecker, K H; Isengard, H D

    2001-06-01

    In the field of reference materials, long-term stability is of highest importance. Particularly for biological matrices, any kind of deterioration must be avoided during shelf-life. In the production precautions are taken to prevent these, but possible alterations caused by intensive drying have been underestimated until today. This presentation discusses several mechanisms of deterioration related to water activity and water content. Comparison of the results for water and moisture for six reference materials and their water sorption isotherms serve as a base to discuss the importance of accurate dry mass corrections for certified values. It is shown that the method chosen for dry mass correction influences certified contents significantly and a method description must be given. Furthermore, it is confirmed that for biological matrices optimal ranges of water activity and water content exist, where hygroscopicity is low without significant danger of product deterioration. Additionally, handling is facilitated in the optimised ranges.

  11. 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.

  12. Determination of ephedrine alkaloids in dietary supplement standard reference materials.

    PubMed

    Sander, Lane C; Sharpless, Katherine E; Satterfield, Mary B; Ihara, Toshihide; Phinney, Karen W; Yen, James H; Wise, Stephen A; Gay, Martha L; Lam, Joseph W; McCooeye, Margaret; Gardner, Graeme; Fraser, Catharine; Sturgeon, Ralph; Roman, Mark

    2005-05-15

    A suite of five ephedra-containing dietary supplement Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST) with certified values for ephedrine alkaloids, synephrine, caffeine, and selected toxic trace elements. The materials represent a variety of natural, extracted, and processed sample matrixes that provide different analytical challenges. The constituents have been determined by multiple independent methods with measurements performed by NIST and by three collaborating laboratories. The methods utilized different sample extraction and cleanup steps in addition to different instrumental analytical techniques and approaches to quantification. In addition, food-matrix proximates were determined by National Food Processor Association laboratories for one of the ephedra-containing SRMs. The SRMs are primarily intended for method validation and for use as control materials to support the analysis of dietary supplements and related botanical materials.

  13. Nondestructive assay of fluorine in geological and other materials by instrumental photon activation analysis with a microtron

    NASA Astrophysics Data System (ADS)

    Krausová, Ivana; Mizera, Jiří; Řanda, Zdeněk; Chvátil, David; Krist, Pavel

    2015-01-01

    Reliable determination of low concentrations of fluorine in geological and coal samples is difficult. It usually requires tedious decomposition and dissolution of the sample followed by chemical conversion of fluorine into its anionic form. The present paper examines possibilities of non-destructive determination of fluorine, mainly in minerals, rocks and coal, by instrumental photon activation analysis (IPAA) using the MT-25 microtron. The fluorine assay consists of counting the positron-electron annihilation line of 18F at 511 keV, which is a product of the photonuclear reaction 19F(γ, n)18F and a pure positron emitter. The assay is complicated by the simultaneous formation of other positron emitters. The main contributors to interference in geological samples are from 45Ti and 34mCl, whereas those from 44Sc and 89Zr are minor. Optimizing beam energy and irradiation-decay-counting times, together with using interfering element calibration standards, allowed reliable IPAA determination of fluorine in selected USGS and CRPG geochemical reference materials, NIST coal reference materials, and NIST RM 8414 Bovine Muscle. In agreement with the published data obtained by PIGE, the results of the F assay by IPAA have revealed erroneous reference values provided for the NIST reference materials SRM 1632 Bituminous Coal and RM 8414 Bovine Muscle. The detection limits in rock and coal samples are in the range of 10-100 μg g-1.

  14. Development of a Thin Film Magnetic Moment Reference Material

    PubMed Central

    Pappas, D. P.; Halloran, S. T.; Owings, R. R.; da Silva, F. C. S.

    2008-01-01

    In this paper we present the development of a magnetic moment reference material for low moment magnetic samples. We first conducted an inter-laboratory comparison to determine the most useful sample dimensions and magnetic properties for common instruments such as vibrating sample magnetometers (VSM), SQUIDs, and alternating gradient field magnetometers. The samples were fabricated and then measured using a vibrating sample magnetometer. Their magnetic moments were calibrated by tracing back to the NIST YIG sphere, SRM 2853. PMID:27096108

  15. Assessment of Effectiveness of Geologic Isolation Systems: REFERENCE SITE INITIAL ASSESSMENT FOR A SALT DOME REPOSITORY

    SciTech Connect

    Harwell, M. A.; Brandstetter, A.; Benson, G. L.; Raymond, J. R.; Brandley, D. J.; Serne, R. J.; Soldat, J. K.; Cole, C. R.; Deutsch, W. J.; Gupta, S. K.; Harwell, C. C.; Napier, B. A.; Reisenauer, A. E.; Prater, L. S.; Simmons, C. S.; Strenge, D. L.; Washburn, J. F.; Zellmer, J. T.

    1982-06-01

    As a methodology demonstration for the Office of Nuclear Waste Isolation (ONWI), the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program conducted an initial reference site analysis of the long-term effectiveness of a salt dome repository. The Hainesville Salt Dome in Texas was chosen to be representative of the Gulf Coast interior salt domes; however, the Hainesville Site has been eliminated as a possible nuclear waste repository site. The data used for this exercise are not adequate for an actual assessment, nor have all the parametric analyses been made that would adequately characterize the response of the geosystem surrounding the repository. Additionally, because this was the first exercise of the complete AEGIS and WASTE Rock Interaction Technology (WRIT) methodology, this report provides the initial opportunity for the methodology, specifically applied to a site, to be reviewed by the community outside the AEGIS. The scenario evaluation, as a part of the methodology demonstration, involved consideration of a large variety of potentially disruptive phenomena, which alone or in concert could lead to a breach in a salt dome repository and to a subsequent transport of the radionuclides to the environment. Without waste- and repository-induced effects, no plausible natural geologic events or processes which would compromise the repository integrity could be envisioned over the one-million-year time frame after closure. Near-field (waste- and repository-induced) effects were excluded from consideration in this analysis, but they can be added in future analyses when that methodology development is more complete. The potential for consequential human intrusion into salt domes within a million-year time frame led to the consideration of a solution mining intrusion scenario. The AEGIS staff developed a specific human intrusion scenario at 100 years and 1000 years post-closure, which is one of a whole suite of possible scenarios. This scenario

  16. Assessment of Effectiveness of Geologic Isolation Systems: REFERENCE SITE INITIAL ASSESSMENT FOR A SALT DOME REPOSITORY

    SciTech Connect

    Harwell, M. A.; Brandstetter, A.; Benson, G. L.; Bradley, D. J.; Serne, R. J.; Soldat, J. K; Cole, C. R.; Deutsch, W. J.; Gupta, S. K.; Harwell, C. C.; Napier, B. A.; Reisenauer, A. E.; Prater, L. S.; Simmons, C. S.; Strenge, D. L.; Washburn, J. F.; Zellmer, J. T.

    1982-06-01

    As a methodology demonstration for the Office of Nuclear Waste Isolation (ONWI), the Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) Program conducted an initial reference site analysis of the long-term effectiveness of a salt dome repository. The Hainesville Salt Dome in Texas was chosen to be representative of the Gulf Coast interior salt domes; however, the Hainesville Site has been eliminated as a possible nuclear waste repository site. The data used for this exercise are not adequate for an actual assessment, nor have all the parametric analyses been made that would adequately characterize the response of the geosystem surrounding the repository. Additionally, because this was the first exercise of the complete AEGIS and WASTE Rock Interaction Technology (WRIT) methodology, this report provides the initial opportunity for the methodology, specifically applied to a site, to be reviewed by the community outside the AEGIS. The scenario evaluation, as a part of the methodology demonstration, involved consideration of a large variety of potentially disruptive phenomena, which alone or in concert could lead to a breach in a salt dome repository and to a subsequent transport of the radionuclides to the environment. Without waste- and repository-induced effects, no plausible natural geologic events or processes which would compromise the repository integrity could be envisioned over the one-million-year time frame after closure. Near-field (waste- and repository-induced) effects were excluded from consideration in this analysis, but they can be added in future analyses when that methodology development is more complete. The potential for consequential human intrusion into salt domes within a million-year time frame led to the consideration of a solution mining intrusion scenario. The AEGIS staff developed a specific human intrusion scenario at 100 years and 1000 years post-closure, which is one of a whole suite of possible scenarios. This scenario

  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. In-house reference material characterization using nuclear methods

    SciTech Connect

    Anderson, D.L.; Cunningham, W.C.

    1994-12-31

    Inclusion of standard reference materials (SRMs) in chemical analysis schemes is an important component of quality control (QC) programs. Effectiveness as QC materials depends on how closely SRM matrices match (in both bulk composition and analyte concentrations) those of the unknowns. For food analysis, wide ranges of matrices and compositions are encountered, and appropriate SRM availability is limited. Moreover, day-to-day use of gram quantities of SRMs during analyses of large numbers of food test samples, such as for the Food and Drug Administration`s (FDA`s) Total Diet Study Program, results in high costs and rapid depletion. To overcome these problems, FDA`s Elemental Research Branch has examined two off-the-shelf foods, soy-based powdered infant formula (SPIF), and cocoa powder, as candidates for in-house (secondary) reference materials. Both materials are relatively homogeneous in particle size and composition and have long shelf lives with no refrigeration. The SPIF is formulated to be a complete infant diet with proper fat content and is fortified with essential vitamins, minerals, and essential elements. At FDA`s Kansas City laboratory, cocoa powder was found to have enough fat to require (desirably) moderate effort for acid digestion and to have cadmium, nickel, and lead concentrations at levels appropriate for graphite furnace atomic absorption spectrometry QC procedures. This material also has suitable concentrations for determination of a number of other elements of interest (e.g., calcium, copper, chromium, iron, potassium, magnesium, manganese, and zinc). Basis weight stabilities, the number of analytes quantitatable by neutron activation methods, and homogeneities for these materials were investigated.

  19. Development of reference materials for SNF NDA systems

    SciTech Connect

    Klann, R. T.

    2000-02-29

    The Department of Energy has over 200 different fuel types which will be placed in a geologic repository for ultimate disposal. At the present time, DOE EM is responsible for assuring safe existing conditions, achieving interim storage, and preparing for final disposition. Each task is governed by regulations which dictate a certain degree of knowledge regarding the contents and condition of the fuel. This knowledge and other associated characteristics are referred to as data needs. It is the stance of DOE EM, that personnel and economic resources are not available to obtain the necessary data to characterize such individual fuel type for final disposal documentation purposes. In addition, it is beyond the need of DOE to do so. This report describes the effort to classify the 200+ fuel types into a subset of fuel types for the purpose of non-destructive analysis (NDA) measurement system development and demonstration testing in support of the DOE National Spent Nuclear Fuel (NSNFP) Program. The fuel types have been grouped into 37 groups based on fuel composition, fuel form, assembly size, enrichment, and other characteristics which affect NDA measurements (e.g., neutron poisons).

  20. 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

  1. Recent developments in food-matrix Reference Materials at NIST.

    PubMed

    Sharpless, K E; Colbert, J C; Greenberg, R R; Schantz, M M; Welch, M J

    2001-06-01

    Since 1996, the National Institute of Standards and Technology (NIST) has developed several food-matrix Standard Reference Materials (SRMs) characterized for nutrient concentrations. These include SRM 1544 Fatty Acids and Cholesterol in a Frozen Diet Composite, SRM 1546 Meat Homogenate, SRM 1548a Typical Diet, SRM 1566b Oyster Tissue, SRM 1846 Infant Formula, and SRM 2383 Baby Food Composite. Three additional materials--SRM 1946 Lake Superior Fish Tissue, SRM 2384 Baking Chocolate, and SRM 2385 Spinach--are in preparation. NIST also recently assigned values for proximate (fat, protein, etc.), individual fatty acid, and total dietary fiber concentrations in a number of existing SRMs and reference materials (RMs) that previously had values assigned for their elemental composition. NIST has used several modes for assignment of analyte concentrations in the food-matrix RMs, including the use of data provided by collaborating laboratories, alone and in combination with NIST data. The use of data provided by collaborating food industry and contract laboratories for the analysis of food-matrix RMs has enabled NIST to provide assigned values for many analytes that NIST does not have the resources or analytical expertise to measure.

  2. 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.

  3. Determination of Mercury in Aqueous and Geologic Materials by Continuous Flow-Cold Vapor-Atomic Fluorescence Spectrometry (CVAFS)

    USGS Publications Warehouse

    Hageman, Philip L.

    2007-01-01

    New methods for the determination of total mercury in geologic materials and dissolved mercury in aqueous samples have been developed that will replace the methods currently (2006) in use. The new methods eliminate the use of sodium dichromate (Na2Cr2O7 ?2H2O) as an oxidizer and preservative and significantly lower the detection limit for geologic and aqueous samples. The new methods also update instrumentation from the traditional use of cold vapor-atomic absorption spectrometry to cold vapor-atomic fluorescence spectrometry. At the same time, the new digestion procedures for geologic materials use the same size test tubes, and the same aluminum heating block and hot plate as required by the current methods. New procedures for collecting and processing of aqueous samples use the same procedures that are currently (2006) in use except that the samples are now preserved with concentrated hydrochloric acid/bromine monochloride instead of sodium dichromate/nitric acid. Both the 'old' and new methods have the same analyst productivity rates. These similarities should permit easy migration to the new methods. Analysis of geologic and aqueous reference standards using the new methods show that these procedures provide mercury recoveries that are as good as or better than the previously used methods.

  4. Application of neutron-activation analysis to geological materials

    SciTech Connect

    Laul, J.C.; Wogman, N.A.

    1980-12-01

    Neutron activation analysis (NAA) is an extremely sensitive, selective, and precise method, which yields a wealth of elemental information from even a small-sized sample. By varying neutron fluxes, irradiation times, decay and counting intervals in instrumental NAA, it is possible to accurately determine about 35 elements in a geological aliquot. When INAA is coupled with coincidence-noncoincidence Ge(Li)-Na(Tl) counting, it enhances the sensitivities of various elements by order of magnitude. The attractive features of INAA are that it is fast, nondestructive and economical.

  5. Agricultural biological reference materials for analytical quality control

    SciTech Connect

    Ihnat, M.

    1986-01-01

    Cooperative work is under way at Agriculture Canada, US Department of Agriculture, and US National Bureau of Standards in an attempt to fill some of the gaps in the world repertoire of reference materials and to provide much needed control materials for laboratories' day to day operations. This undertaking involves the preparation and characterization of a number of agricultural and food materials for data quality control for inorganic constituents. Parameters considered in the development of these materials were material selection based on importance in commerce and analysis; techniques of preparation, processing, and packaging; physical and chemical characterization; homogeneity testing and quantitation (certification). A large number of agricultural/food products have been selected to represent a wide range of not only levels of sought-for constituents (elements) but also a wide range of matrix components such as protein, carbohydrate, dietary fiber, fat, and ash. Elements whose concentrations are being certified cover some two dozen major, minor, and trace elements of nutritional, toxicological, and environmental significance.

  6. New technique for the determination of trace noble metal content in geological and process materials

    NASA Astrophysics Data System (ADS)

    Mitkin, V. N.; Zayakina, S. B.; Anoshin, G. N.

    2003-02-01

    A new two-step sample preparation technique is proposed for the instrumental determination of trace quantities of noble metals (NM) in refractory geological and process materials. The decomposition procedure is based on the oxidizing fluorination of samples with subsequent sulfatization (OFS) of the sample melt or cake. Fluorination of samples is accomplished using a mixture of KHF 2+KBrF 4 or KHF 2+BrF 3 depending on the ratio of sample mass to oxidizing mixture. Both cakes and melts can result using this procedure. Sulfatization of resulting fluorides is completed using concentrated sulfuric acid heated to 550 °C. Validation studies using certified geostandard reference materials (GSO VP-2, ZH-3, Matte RTP, HO-1, SARM-7) have shown that the proposed method is fast, convenient and most often produces non-hygroscopic homogeneous residues suitable for analysis by atomic absorption spectrometry (AAS) and atomic emission spectrometry (AES). Results obtained for NM concentrations in reference materials agreed with certified concentration ranges and results obtained using other methods of analysis. The OFS procedure combined with direct current plasma d.c. plasma AES achieved the following limits of detection (LOD) for the noble metals: Ag, Au, Pd, 1-2×10 -6; Pt, 5×10 -6; and Ru, Rh, Ir, Os, 1-3×10 -7 wt.%. Using graphite furnace AAS (GFAAS) combined extraction pre-concentration the following LODs for NMs were achieved: Pt, Ru, 1×10 -6; Pd, Rh, 1×10 -7; and Au, Ag, 1-2×10 -8 wt.%. The relative standard deviation for NM determinations ( Sr) was dependent on NM concentration and sample type, but commonly was in the range of 3-15% for d.c. plasma AES and 5-30% for GFAAS.

  7. Mapping watershed potential to contribute phosphorus from geologic materials to receiving streams, southeastern United States

    USGS Publications Warehouse

    Terziotti, Silvia; Hoos, Anne B.; Harned, Douglas; Garcia, Ana Maria

    2010-01-01

    As part of the southeastern United States SPARROW (SPAtially Referenced Regressions On Watershed attributes) water-quality model implementation, the U.S. Geological Survey created a dataset to characterize the contribution of phosphorus to streams from weathering and erosion of surficial geologic materials. SPARROW provides estimates of total nitrogen and phosphorus loads in surface waters from point and nonpoint sources. The characterization of the contribution of phosphorus from geologic materials is important to help separate the effects of natural or background sources of phosphorus from anthropogenic sources of phosphorus, such as municipal wastewater or agricultural practices. The potential of a watershed to contribute phosphorus from naturally occurring geologic materials to streams was characterized by using geochemical data from bed-sediment samples collected from first-order streams in relatively undisturbed watersheds as part of the multiyear U.S. Geological Survey National Geochemical Survey. The spatial pattern of bed-sediment phosphorus concentration is offered as a tool to represent the best available information at the regional scale. One issue may weaken the use of bed-sediment phosphorus concentration as a surrogate for the potential for geologic materials in the watershed to contribute to instream levels of phosphorus-an unknown part of the variability in bed-sediment phosphorus concentration may be due to the rates of net deposition and processing of phosphorus in the streambed rather than to variability in the potential of the watershed's geologic materials to contribute phosphorus to the stream. Two additional datasets were created to represent the potential of a watershed to contribute phosphorus from geologic materials disturbed by mining activities from active mines and inactive mines.

  8. Determination of vitamins in food-matrix Standard Reference Materials.

    PubMed

    Sharpless, K E; Margolis, S; Thomas, J B

    2000-06-09

    In recent years, the National Institute of Standards and Technology (NIST) has developed several food-matrix Standard Reference Materials (SRMs) characterized for vitamins and other organic nutrients. NIST uses several "modes" for assignment of analyte concentrations in SRMs, one of which includes the use of data provided by collaborating laboratories. Certification modes and liquid chromatographic methods that were used by NIST for value assignment of vitamin concentrations in recently introduced food-matrix SRMs are described in this paper. These materials and methods include vitamins D and E in coconut oil (SRM 1563) by gravimetry and multi-dimensional liquid chromatography (LC); vitamins A, E, and several B vitamins by reversed-phase LC and vitamin C by ion-exchange chromatography in infant formula (SRM 1846); and carotenoids and vitamins A and E by reversed-phase liquid chromatography in a baby food composite (SRM 2383).

  9. 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.

  10. 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

  11. Analysis on the use of engineered barriers for geologic isolation of spent fuel in a reference salt site repository

    SciTech Connect

    Cloninger, M.O.; Cole, C.R.; Washburn, J.F.

    1980-12-01

    A perspective on the potential durability and effectiveness requirements for the waste form, container and other engineered barriers for geologic disposal of spent nuclear fuel has been developed. This perspective is based on calculated potential doses to individuals who may be exposed to radioactivity released from a repository via a groundwater transport pathway. These potential dose commitments were calculated with an integrated geosphere transport and bioshpere transport model. A sensitivity analysis was accomplished by varying four important system parameters, namely the waste radionuclide release rate from the repository, the delay prior to groundwater contact with the waste (leach initiation), aquifer flow velocity and flow path length. The nuclide retarding capacity of the geologic media, a major determinant of the isolation effectiveness, was not varied as a parameter but was held constant for a particular reference site. This analysis is limited to looking only at engineered barriers whose net effect is either to delay groundwater contact with the waste form or to limit the rate of release of radionuclides into the groundwater once contact has occurred. The analysis considers only leach incident scenarios, including a water well intrusion into the groundwater near a repository, but does not consider other human intrusion events or catastrophic events. The analysis has so far been applied to a reference salt site repository system and conclusions are presented.Basically, in nearly all cases, the regional geology is the most effective barrier to release of radionuclides to the biosphere; however, for long-lived isotopes of carbon, technetium and iodine, which were poorly sorbed on the geologic media, the geology is not very effective once a leach incident is initiated.

  12. 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

  13. Processing of Neutron Diffraction Data for Strain Measurement in Geological Materials

    SciTech Connect

    Polsky, Yarom; An, Ke; Anovitz, Lawrence {Larry} M; Bingham, Philip R; Carmichael, Justin R; Dessieux Jr, Luc Lucius

    2014-01-01

    : Conventional rock mechanics testing techniques typically involve the loading of samples and measurement of displacements or strains on the outer boundary of the specimen surface. Neutron diffraction based strain measurement techniques represent a unique and powerful tool for measuring the strain within geological materials under load. The structural variability and non-uniform crystallinity of geological materials, however, create many complexities in the intensity patterns that must be analyzed to quantify strains within the material. The attenuating and scattering properties of the pressure cell housing the sample further add difficulties to the data analysis. This paper describes the methods and processes used to process neutron scattering data for strain measurement in geological materials. It is intended to provide a primer for those in the rock mechanics community that are interested in utilizing this technique along with additional discussion of neutron diffraction experimental factors that may affect data quality.

  14. Certification of nutrients in Standard Reference Material 1846: infant formula.

    PubMed

    Sharpless, K E; Schiller, S B; Margolis, S A; Thomas, J B; Iyengar, G V; Colbert, J C; Gills, T E; Wise, S A; Tanner, J T; Wolf, W R

    1997-01-01

    In 1996, the National Institute of Standards and Technology (NIST) released Standard Reference Material 1846 (Infant Formula), which can be used as a control material for assigning values to in-house control materials and for validating analytical methods for measurement of proximates, vitamins, and minerals in infant formula and similar matrixes. The SRM was manufactured by preparing a spray-dried formula base containing fat, protein, carbohydrates, and minerals and then combining that formula base with a dry-blend vitamin premix that supplied the vitamins. The Certificate of Analysis for SRM 1846 provides assigned values for concentrations of proximates (fat, protein, etc.), vitamins, and minerals for which product labeling is required by the Infant Formula Act of 1980 and by the Nutrition Labeling and Education Act of 1990. These assigned values were based on agreement of measurements by NIST and/or collaborating laboratories. Certified values are provided for vitamins A (trans), E, C, B2, and B6 and niacin. Noncertified values are provided for solids, ash, fat, nitrogen, protein, carbohydrate, calories, vitamin D, delta-tocopherol, gamma-tocopherol, vitamin B1, vitamin B12, folic acid, pantothenic acid, biotin, choline, inositol, calcium, phosphorus, magnesium, iron, zinc, copper, sodium, potassium, and chloride. Information values are provided for iodine, manganese, selenium, and vitamin K.

  15. Certification of standard reference materials containing bitter orange.

    PubMed

    Sander, L C; Putzbach, K; Nelson, B C; Rimmer, C A; Bedner, M; Thomas, J Brown; Porter, B J; Wood, L J; Schantz, M M; Murphy, K E; Sharpless, K E; Wise, S A; Yen, J H; Siitonen, P H; Evans, R L; Nguyen Pho, A; Roman, M C; Betz, J M

    2008-07-01

    A suite of three dietary supplement standard reference materials (SRMs) containing bitter orange has been developed, and the levels of five alkaloids and caffeine have been measured by multiple analytical methods. Synephrine, octopamine, tyramine, N-methyltyramine, hordenine, total alkaloids, and caffeine were determined by as many as six analytical methods, with measurements performed at the National Institute of Standards and Technology and at two collaborating laboratories. The methods offer substantial independence, with two types of extractions, two separation methods, and four detection methods. Excellent agreement was obtained among the measurements, with data reproducibility for most methods and analytes better than 5% relative standard deviation. The bitter-orange-containing dietary supplement SRMs are intended primarily for use as measurement controls and for use in the development and validation of analytical methods.

  16. Transportation of reagents, reference materials and samples: the international perspective.

    PubMed

    Pearson, J E; Edwards, S

    2006-01-01

    The International Regulations for the transport of infectious substances, which could include reagents, reference material and samples, are based on the 13th revision of the United Nations Model Regulations and are the standard for transport of infectious substances by all means of transportation. The 13th revision, effective January 2005 and further amended in March and July 2005, made major improvements in these shipping regulations. They specifically exempt certain substances, including those that have been neutralized or inactivated to destroy any pathogens and samples from "normal" animals. Infectious substances are divided into Category A, which includes primarily cultures of the more pathogenic agents and Category B, which includes all other substances that do not meet the Category A criteria. Tissue specimens, submitted for diagnosis, are included in Category B. Category A shipments must have a Dangerous Goods Certificate and meet other requirements; Category B shipments do not. The National requirements, such as import permits, and certain airline restrictions must also be met.

  17. 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).

  18. 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.

  19. 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.

  20. Reference analysis on the utility of engineered barriers for geologic disposal of spent nuclear fuel: overview

    SciTech Connect

    Cloninger, M.O.

    1981-09-01

    The development and characterization of waste forms, containers and other engineered barriers destined for use in the isolation of nuclear waste in deep geologic repositories has progressed to the point where there are several options for barrier systems that are available to help assure safe disposal of nuclear wastes. However, a rigorous basis has not yet developed to define whether various concepts or products are required or desirable, or how effective they should be for how long. This analysis is an attempt to contribute to that basis. Intent of the study is to determine what incentives exist for providing highly effective engineered barriers for the isolation of radioactive waste (spent fuel in this case) in a deep geologic repository. 6 figures.

  1. Medical geology in tropical countries with special reference to Sri Lanka.

    PubMed

    Dissanayake, C B; Chandrajith, Rohana

    2007-04-01

    Sri Lanka provides an ideal opportunity for the study of the effect of geology on human health. The vast majority of the people of Sri Lanka still live in rural areas within areas termed geochemical provinces. Very broadly, one could say that a geochemical province has characteristic chemical composition in soil, water stream sediments and rocks, enabling their delineation from others. The chemical composition is presumed to be have an impact on the health of the inhabitants of the particular geochemical province, particularly because of the fact that their food and water are obtained mostly from the terrain itself. This leads to the concept of "diseases of geochemical origin". Among these are dental fluorosis, iodine deficiency disorders (IDDs) and selenium-based diseases. The Dry Zone of Sri Lanka has several areas rich in groundwater fluoride, the ingestion of which leads to dental fluorosis. Iodine deficiency diseases are more common in the Wet Zone, though their aetiologies are more complicated. Interestingly, it has also been observed that significant proportions of the female population of Sri Lanka are selenium-deficient, which could well be related to the geological environment. Chronic renal failure (CRF) has been observed in some areas of the Dry Zone of Sri Lanka, where there is a relationship of CRF with the mineral content of drinking water. This subject matter falls under the auspices of Medical Geology, a scientific discipline still in its infancy, and much more concerted studies are needed to attract the attention of medical research.

  2. Bottom-up effects of geologic parent material through ecological interaction webs

    NASA Astrophysics Data System (ADS)

    Bradley, R.

    2012-04-01

    Community ecologists study the interactions between species to understand what controls the distribution and abundance of different populations. Communities are thus portrayed as "interaction webs", in which different species exert reciprocal pressures on each other. In the case of one population being a resource for which another population is the consumer (i.e. food-web), reciprocal pressures are commonly referred to as "bottom-up" vs. "top-down" effects. The starting point for studying bottom-up effects is usually the vegetation (primary producers), and its end-point the decomposer community responsible for breaking down detrital matter from each trophic level. In my presentation, I will present results from three former graduate students, to argue that the starting point for studying bottom-up effects should be the geologic parent material (GPM), whose importance has often been overlooked by community ecologists. For example, our data show that GPM had a stronger effect on forest floor nutrient budgets than the identity or successional stage of the vegetation. Likewise, GPM had a strong effect on the structure of forest floor microbial communities, as well as their resistance to, and resilience from, disturbance. GPM also had a significant effect on the richness and diversity of understory plant communities from similar forest stands. Finally, we present evidence that soil fertility controls the resistance and tolerance of certain plant species to selective browsing, thereby affecting the composition of the dominant plant cover and the feeding patterns of large herbivores.

  3. 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

  4. Development of reference conditions for geologic repositories for nuclear waste in the USA

    SciTech Connect

    Raines, G. E.; Rickertsen, L. D.; Claiborne, H. C.; McElroy, J. L.; Lynch, R. W.

    1980-10-01

    Activities to determine interim reference conditions for temperatures, pressure, fluid, chemical, and radiation environments that are expected to exist in commercial and defense high-level nuclear waste and spent fuel repositories in salt, basalt, tuff, granite, and shale are summarized. These interim conditions are being generated by the Reference Repository Conditions Interface Working Groups (RRC-IWG), an ad hoc IWG established by the National Waste Terminal Storage Program's (NWTS) Isolation Interface Control Board (I-ICB).

  5. Primary and secondary reference materials for procedures to test the quality of medicines and foods.

    PubMed

    Hauck, Walter W

    2012-04-01

    At present a complex global patchwork of private and public monographs and reference materials is variously available to help ensure the quality of medicines and foods. The relationship of these monographs and reference materials, one to another, frequently is inconsistently understood and documented.This article considers the complexity of monographs and reference materials with a focus on qualifying one reference material relative to another.

  6. The development and certification of Standard Reference Materials (SRMs) to assess and ensure accurate measurement of Pb in the environment.

    PubMed

    Fassett, J D; MacDonald, B S

    2001-08-01

    The National Institute of Standards and Technology (NIST) has had a major quality-assurance role in the federal effort to reduce lead poisoning of children in the United States through its mission of ensuring the accuracy of chemical measurements. NIST certifies reference materials (standard reference materials--SRMs) that are used to benchmark measurements by secondary and field methods of analysis--to ensure that decisions of great health and economic impact are soundly based on good measurement science. Over the past 10 years, in cooperation with the US Environmental Protection Agency (EPA), US Department of Housing and Urban Development (HUD), and the United States Geological Survey (USGS), NIST has prepared and certified SRMs for lead content in soil, indoor dust, and paint. The role of these materials in meeting regulatory and abatement needs is described and their certified values are summarized.

  7. 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.

  8. Standard Reference Materials for dioxins and other environmental pollutants.

    PubMed

    Alvarez, R

    1991-05-01

    The National Institute of Standards and Technology issues approximately 1100 Standard Reference Materials (SRMs) certified for chemical composition or physical properties. A number of these SRMs has been developed to assist chemists in analyzing environmental samples more reliably for chlorinated dioxins and other organic pollutants. Certification of the pollutant concentration in a natural matrix SRM is based on concordant analyses by the NIST Organic Analytical Research Division using at least two independent methods. For a calibration solution, such as SRM 1614, Dioxin (2,3,7,8-TCDD) in Isooctane, certification is based on agreement of the calculated concentration based on the gravimetric preparation and the concentration as determined experimentally. SRM 1614 also includes a 13C-labeled 2,3,7,8-TCDD for use as an internal standard in methods based on gas chromatography/mass spectrometry. The certified concentrations (ng g-1) are 98.3 +/- 3.3 for the unlabeled dioxin and 95.6 +/- 1.5 for the labeled dioxin. The certificates for SRM 1588, Organics in Cod Liver Oil, and SRM 1589, Polychlorinated Biphenyls (as Aroclor 1260) in Human Serum, provide noncertified concentrations of dioxins. Concentrations of chlorinated dioxins in two urban particulate SRMs have been reported in the literature.

  9. Reference material manufacture and certification for the AVNG

    SciTech Connect

    Hauck, Danielle K; Thron, Jonathan; MacArthur, Duncan W.; Livke, Alexander; Bulatov, M; Kondratov, Sergey; Leplyavkina, M; Razinkov, Sergey; Sivachev, D; Tsybryaev, S; V'yushin, A

    2010-07-09

    Testing and demonstration of any radiation measurement system requires the use of appropriate radioactive sources. An attribute measurement system (A VNG) was developed and fabricated at the Russian Federal Nuclear Center, VNIIEF, Russia, under contract with LANL, USA. The A VNG detects neutron and gamma radiation signatures and compares the data analysis results with the specified threshold values for three unclassified attributes; plutonium is present or absent, plutonium mass is greater than or less than the specified threshold value and plutonium isotopic ratio 240Pu to 239Pu) is greater than or less then the threshold value. A set of reference materials (RMs) was specially manufactured for the A VNG with masses and isotopic ratios above and below the selected thresholds. The set of RMs was certified in compliance with the Russian metrological requirements. The RMs were used to debug and test the A VNG and to demonstrate the A VNG operation to an American delegation in June 2009. In this presentation, we will describe the various steps in the manufacture and certification of these RM sources.

  10. Development of a southern oceanic air standard reference material.

    PubMed

    Rhoderick, George C; Kelley, Michael E; Miller, Walter R; Brailsford, Gordon; Possolo, Antonio

    2016-02-01

    In 2009, the United States Congress charged the National Institute of Standards and Technology (NIST) with supporting climate change research. As part of this effort, the Gas Sensing Metrology Group at NIST began developing new gas standard mixtures for greenhouse gas mixtures relevant to atmospheric measurements. Suites of gravimetrically prepared primary standard mixtures (PSMs) were prepared at ambient concentration levels for carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in a dry-air balance. In parallel, 30 gas cylinders were filled, by the National Institute of Water and Atmospheric Research (NIWA) in Wellington, New Zealand, to high pressure from pristine southern oceanic air at Baring Head, New Zealand, and shipped to NIST. Using spectroscopic instrumentation, NIST analyzed the 30 cylinder samples for mole fractions of CO2, CH4, and N2O. Certified values were assigned to these mixtures by calibrating the instrumentation with the PSM suites that were recently developed at NIST. These mixtures became NIST Standard Reference Material (SRM) 1721 Southern Oceanic Air and are certified for ambient mole fraction, the first of their kind for NIST. The relative expanded uncertainties corresponding to coverage intervals with 95% probability are no larger than 0.06% of the certified values, representing the smallest uncertainties to date ever assigned to an NIST gas SRM.

  11. 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.

  12. Are There any Satisfactory Geological Analogues for a Future Greenhouse Warming: with Special Reference to the Pliocene

    NASA Astrophysics Data System (ADS)

    Haywood, A. M.; Ridgwell, A. J.; Lunt, D. J.; Hill, D. J.; Dowsett, H. J.; Williams, M.

    2010-12-01

    Given the inherent uncertainties in predicting the climate and environmental response to anthropogenic emissions of greenhouse gases, it would be highly beneficial to society if science could identify geological analogues to the human races current grand climate experiment. Unsurprisingly this has been a focus of the geological and palaeoclimate communities over the last thirty years, with many scientific papers claiming that intervals in Earth history can be used as an analogue for future climate change. Using a coupled ocean-atmosphere modelling approach we test this assertion for the most likely pre-Quaternary candidates within the last 100 million years with a particular focus on warm 'interglacial' events within the Pliocene epoch. In all instances these intervals, including Pliocene interglacials, fail as true analogues since they either represent equilibrium climate states to a long-term greenhouse gas forcing, whereas anthropogenic emissions of greenhouse gases provide a progressive (transient) forcing on climate, or the sensitivity of the climate system itself to greenhouse gasses was different in the past due to tectonic and other factors. Therefore, we conclude that there are no satisfactory pre-Quaternary geological analogues for a future greenhouse warming. References to geological analogues should be abandoned and replaced by the investigation of processes operating during warm climate states. The relevance of warm intervals in Earth history, including the Pliocene, is not in the assessment of climate sensitivity, nor is it in the vain search for a direct analogue for late 21st century climate. The strength of pre-Quaternary palaeoclimate studies, and Pliocene research in particular, is in (a) the assessment and calculation of the response of global temperatures to increasing greenhouse gas concentrations in the longer term (multiple centuries), what we term the Earth System Sensitivity, and (b) in the assessment of the abilities of climate and Earth

  13. 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.

  14. 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

  15. 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

  16. 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

  17. New Ca-Tims and La-Icp Analyses of GJ-1, Plesovice, and FC1 Reference Materials

    NASA Astrophysics Data System (ADS)

    Feldman, J. D.; Möller, A.; Walker, J. D.

    2014-12-01

    Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb zircon geochronology relies on external reference standards to monitor and correct for different mass fractionation effects and instrument drift. Common zircon reference materials used within the community, including the KU Isotope Geochemistry Laboratory, are GJ-1 (207Pb/206Pb age: 608.53 +/- 0.37Ma; Jackson et al., 2004), Plesovice (337.13 +/- 0.37 Ma; Slama et al., 2008), and FC-1 (1099.0 +/-0.6 Ma; Paces and Miller, 1993). The age distribution of zircon reference material varies slightly from sample fraction to sample fraction, and the published results for GJ-1 are slightly discordant. As a result, using the published data for the distributed standard splits can lead to small systematic variations when comparing datasets from different labs, and more high precision data are needed to evaluate potential inhomogeneity of sample splits used in different laboratories. Here we characterize these reference materials with cathodoluminescence, LA-ICP-MS traverses across grains, and high precision CA-TIMS to better constrain the ages and assess zoning of these standards, and present the data for comparison with other laboratories. Reducing systematic error by dating our own reference material lends confidence to our analyses and allows for inter-laboratory age reproducibility of unknowns. Additionally, the reduction in propagated uncertainties (especially in GJ-1, for which both the red and yellow variety will be analyzed) will be used to improve long-term reproducibility, comparisons between samples of similar age, detrital populations and composite pluton zircons. Jackson, S.E., et al., 2004, Chemical Geology, v. 211, p. 47-69. Paces, J.B. & Miller, J.D., 1993, Journal of Geophysical Research, v. 80, p. 13997-14013. Slama, J., et al., 2008, Chemical Geology, v. 249. p. 1-35.

  18. Certification of the chlorine content of the isotopic reference materials IRMM-641 and IRMM-642.

    PubMed

    Ostermann, M; Berglund, M; Taylor, P D; Máriássy, M

    2001-11-01

    The Slovak Institute of Metrology and the Institute for Reference Materials and Measurements have collaborated in the certification of the two chlorine reference materials IRMM-641 and IRMM-642. Until now no isotopically enriched chlorine isotopic reference material certified for isotopic composition and content has been available commercially. The isotopic reference materials IRMM-641 and IRMM-642 described herein are certified for isotopic composition and for chlorine content. The chlorine content of the reference material IRMM-641 was certified by use of high-precision argentometric coulometric titration at the Slovak Institute of Metrology. The base material used for IRMM-641 is NIST Standard Reference Material 975. The chlorine content of the reference material IRMM-642 was measured by isotope dilution, using negative thermal ionization mass spectrometry at the Institute for Reference Materials and Measurements. Both standard reference materials were prepared by dissolving NaCl in water. The reference material IRMM-641 contains 0.025022 +/- 0.00011 mol kg(-1) chlorine of natural isotopic composition with an n(37Cl)/n(35Cl) ratio of 0.31977 +/- 0.00082. The reference material IRMM-642 contains 0.004458 +/- 0.000028 mol kg(-1) chlorine with an n(37Cl)/n(35Cl) ratio of 0.01914 +/- 0.00088.

  19. Archean, Paleoproterozoic and Mesoproterozoic Crust of Central East Antarctica: New Insights on Subglacial Geology from Proxy Geologic Materials

    NASA Astrophysics Data System (ADS)

    Goodge, J. W.; Fanning, C. M.; Vervoort, J. D.; Fisher, C. M.; Nissen, C. I.

    2013-12-01

    Uncovering the ice-covered geology of East Antarctica is critical for understanding its ancient crustal history, its role in supercontinent formation, and its relationship to development of the Cenozoic ice cap. Multiple approaches--including detrital-mineral provenance study, analysis of glacial clasts, airborne and passive geophysics, and future sub-ice drilling--are rapidly improving our view of the remote continental interior. Proxy geologic materials such as detrital zircons and glacial clasts provide indirect means to sample the ice-covered crust, although spatial-geographic resolution is poor; geophysical data are spatially accurate yet limited by uncertainty in geologic significance. In addition to U-Pb zircon ages of ~3.1, 2.5 and 1.7 Ga from Nimrod Group outcrop, detrital-zircon provenance and glacial clast studies from the central Transantarctic Mountains show that central East Antarctica was formed by a series of episodic magmatic events at 2.01, 1.88-1.79, 1.57, 1.48-1.43, and 1.22-1.06 Ga. Zircon Hf and O isotopic compositions from a suite of granitoid clasts collected from glacial catchments draining central East Antarctica have variable compositions that indicate both juvenile, mantle-derived melts and those involving older crustal sources. None of these igneous clast ages are known from limited Antarctic outcrop in the region. Detrital zircon ages in Neoproterozoic rift-margin strata confirm important populations of 1.88-1.72, 1.64-1.36, and 1.28-1.04 Ga, strengthening a case for episodic magmatic growth of East Antarctic crust. After a juvenile Archean magmatic origin, central East Antarctica was consolidated by further crustal assembly at ~1.9 (Nuna time), ~1.7 (Mawson), and ~1.2 Ga (Rodinia), as indicated by monazite U-Pb ages from metamorphic leucogneiss clasts. Monazite ages record suspected but previously undocumented Proterozoic tectonometamorphic events in central East Antarctica, overprinted by younger Neoproterozoic metamorphism. Together

  20. Cold dissolution method for the determination of uranium in various geological materials at trace levels by laser fluorimetry.

    PubMed

    Ramdoss, K; Amma, B G; Umashankar, V; Rangaswamy, R

    1997-06-01

    A cold dissolution procedure for the determination of uranium in various geological materials like rocks, minerals, soils etc., has been described. Samples are allowed to react with HF and HNO(3) at room temperature overnight. Boric acid is added to complex excess fluoride ions. From the clear solution thus obtained, uranium is determined directly in laser fluorimeter after the addition of fluorescence enhancing reagents. The results of few standard reference materials analysed by the present method agree with the certified values. This methodology does not require platinum or teflon ware, exhaust system and time consuming solvent extraction step. Hazardous acid vapours are not left in air, so there is no air pollution. Chemicals consumption is minimal. Therefore the method is economical. The method can be employed for high sample throughput which is the prerequisite for exploration geochemists.

  1. 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.

  2. Geologic utility of improved orbital measurement capabilities in reference to non-renewable resources

    NASA Technical Reports Server (NTRS)

    Stewart, H.; Marsh, S.

    1982-01-01

    Spectral and spatial characteristics necessary for future orbital remote sensing systems are defined. The conclusions are based on the past decade of experience in exploring for non-renewable resources with reference to data from ground, aircraft, and orbital systems. Two principle areas of investigation are used in the discussion: a structural interpretation in a basin area for hydrocarbon exploration, and a discrimination of altered areas in the Cuprite district in Nevada.

  3. 46 CFR 164.008-1 - Applicable specification and reference material.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Applicable specification and reference material. 164.008-1 Section 164.008-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL MATERIALS Bulkhead Panels § 164.008-1 Applicable specification and reference material....

  4. Evaluation of stream chemistry trends in US Geological Survey reference watersheds, 1970-2010.

    PubMed

    Mast, M Alisa

    2013-11-01

    The Hydrologic Benchmark Network (HBN) is a long-term monitoring program established by the US Geological Survey in the 1960s to track changes in the streamflow and stream chemistry in undeveloped watersheds across the USA. Trends in stream chemistry were tested at 15 HBN stations over two periods (1970-2010 and 1990-2010) using the parametric Load Estimator (LOADEST) model and the nonparametric seasonal Kendall test. Trends in annual streamflow and precipitation chemistry also were tested to help identify likely drivers of changes in stream chemistry. At stations in the northeastern USA, there were significant declines in stream sulfate, which were consistent with declines in sulfate deposition resulting from the reductions in SO₂ emissions mandated under the Clean Air Act Amendments. Sulfate declines in stream water were smaller than declines in deposition suggesting sulfate may be accumulating in watershed soils and thereby delaying the stream response to improvements in deposition. Trends in stream chemistry at stations in other part of the country generally were attributed to climate variability or land disturbance. Despite declines in sulfate deposition, increasing stream sulfate was observed at several stations and appeared to be linked to periods of drought or declining streamflow. Falling water tables might have enhanced oxidation of organic matter in wetlands or pyrite in mineralized bedrock thereby increasing sulfate export in surface water. Increasing sulfate and nitrate at a station in the western USA were attributed to release of soluble salts and nutrients from soils following a large wildfire in the watershed.

  5. Evaluation of stream chemistry trends in US Geological Survey reference watersheds, 1970-2010

    USGS Publications Warehouse

    Mast, M. Alisa

    2013-01-01

    The Hydrologic Benchmark Network (HBN) is a long-term monitoring program established by the US Geological Survey in the 1960s to track changes in the streamflow and stream chemistry in undeveloped watersheds across the USA. Trends in stream chemistry were tested at 15 HBN stations over two periods (1970–2010 and 1990–2010) using the parametric Load Estimator (LOADEST) model and the nonparametric seasonal Kendall test. Trends in annual streamflow and precipitation chemistry also were tested to help identify likely drivers of changes in stream chemistry. At stations in the northeastern USA, there were significant declines in stream sulfate, which were consistent with declines in sulfate deposition resulting from the reductions in SO2 emissions mandated under the Clean Air Act Amendments. Sulfate declines in stream water were smaller than declines in deposition suggesting sulfate may be accumulating in watershed soils and thereby delaying the stream response to improvements in deposition. Trends in stream chemistry at stations in other part of the country generally were attributed to climate variability or land disturbance. Despite declines in sulfate deposition, increasing stream sulfate was observed at several stations and appeared to be linked to periods of drought or declining streamflow. Falling water tables might have enhanced oxidation of organic matter in wetlands or pyrite in mineralized bedrock thereby increasing sulfate export in surface water. Increasing sulfate and nitrate at a station in the western USA were attributed to release of soluble salts and nutrients from soils following a large wildfire in the watershed.

  6. Reference Materials in LIS Instruction: A Delphi Study

    ERIC Educational Resources Information Center

    Rabina, Debbie

    2013-01-01

    This paper presents the results of a Delphi study conducted over a two-month period in 2011. The purpose of the study was to identify reference sources that should be covered in basic reference courses taught in LIS programs in the United States. The Delphi method was selected for its appropriateness in soliciting expert opinions and assessing the…

  7. Determination of total tin in geological materials by electrothermal atomic-absorption spectrophotometry using a tungsten-impregnated graphite furnace

    USGS Publications Warehouse

    Zhou, L.; Chao, T.T.; Meier, A.L.

    1984-01-01

    An electrothermal atomic-absorption spectrophotometric method is described for the determination of total tin in geological materials, with use of a tungsten-impregnated graphite furnace. The sample is decomposed by fusion with lithium metaborate and the melt is dissolved in 10% hydrochloric acid. Tin is then extracted into trioctylphosphine oxide-methyl isobutyl ketone prior to atomization. Impregnation of the furnace with a sodium tungstate solution increases the sensitivity of the determination and improves the precision of the results. The limits of determination are 0.5-20 ppm of tin in the sample. Higher tin values can be determined by dilution of the extract. Replicate analyses of eighteen geological reference samples with diverse matrices gave relative standard deviations ranging from 2.0 to 10.8% with an average of 4.6%. Average tin values for reference samples were in general agreement with, but more precise than, those reported by others. Apparent recoveries of tin added to various samples ranged from 95 to 111% with an average of 102%. ?? 1984.

  8. The group separation of the rare-earth elements and yttrium from geologic materials by cation-exchange chromatography

    USGS Publications Warehouse

    Crock, J.G.; Lichte, F.E.; Wildeman, T.R.

    1984-01-01

    Demand is increasing for the determination of the rare-earth elements (REE) and yttrium in geologic materials. Due to their low natural abundance in many materials and the interferences that occur in many methods of determination, a separation procedure utilizing gradient strong-acid cation-exchange chromatography is often used to preconcentrate and isolate these elements from the host-rock matrix. Two separate gradient strong-acid cation-exchange procedures were characterized and the major elements as well as those elements thought to provide the greatest interference for the determination of the REE in geologic materials were tested for separation from the REE. Simultaneous inductively coupled argon plasma-atomic emission spectroscopy (ICAP-AES) measurements were used to construct the chromatograms for the elution studies, allowing the elution patterns of all the elements of interest to be determined in a single fraction of eluent. As a rock matrix, U.S. Geological Survey standard reference BCR-1 basalt was digested using both an acid decomposition procedure and a lithium metaborate fusion. Hydrochloric and nitric acids were tested as eluents and chromatograms were plotted using the ICAP-AES data; and we observed substantial differences in the elution patterns of the REE and as well as in the solution patterns of Ba, Ca, Fe and Sr. The nitric acid elution required substantially less eluent to elute the REE and Y as a group when compared to the hydrochloric acid elution, and provided a clearer separation of the REE from interfering and matrix elements. ?? 1984.

  9. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 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...

  10. 10 CFR 431.223 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 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...

  11. 10 CFR 431.15 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INDUSTRIAL EQUIPMENT Electric Motors Test Procedures, Materials Incorporated and Methods of Determining... following test procedures into subpart B of part 431. The material listed in paragraph (b) of this section... organization will not affect the DOE test procedures unless and until amended by DOE. Material is...

  12. 10 CFR 431.15 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INDUSTRIAL EQUIPMENT Electric Motors Test Procedures, Materials Incorporated and Methods of Determining... following test procedures into Subpart B of Part 431. The material listed in paragraph (b) of this section... organization will not affect the DOE test procedures unless and until amended by DOE. Material is...

  13. Geology and insolation-driven climatic history of Amazonian north polar materials on Mars

    USGS Publications Warehouse

    Tanaka, K.L.

    2005-01-01

    Mariner 9 and Viking spacecraft images revealed that the polar regions of Mars, like those of Earth, record the planet's climate history. However, fundamental uncertainties regarding the materials, features, ages and processes constituting the geologic record remained. Recently acquired Mars Orbiter Laser Altimeter data and Mars Orbiter Camera high-resolution images from the Mars Global Surveyor spacecraft and moderately high-resolution Thermal Emission Imaging System visible images from the Mars Odyssey spacecraft permit more comprehensive geologic and climatic analyses. Here I map and show the history of geologic materials and features in the north polar region that span the Amazonian period (???3.0 Gyr ago to present). Erosion and redeposition of putative circumpolar mud volcano deposits (formed by eruption of liquefied, fine-grained material) led to the formation of an Early Amazonian polar plateau consisting of dark layered materials. Crater ejecta superposed on pedestals indicate that a thin mantle was present during most of the Amazonian, suggesting generally higher obliquity and insolation conditions at the poles than at present. Brighter polar layered deposits rest unconformably on the dark layers and formed mainly during lower obliquity over the past 4-5 Myr (ref. 20). Finally, the uppermost layers post-date the latest downtrend in obliquity <20,000 years ago. ?? 2005 Nature Publishing Group.

  14. Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 2: Shellfish Matrix Materials.

    PubMed

    McCarron, Pearse; Reeves, Kelley L; Giddings, Sabrina D; Beach, Daniel G; Quilliam, Michael A

    2016-09-01

    Okadaic acid (OA) and its analogs, dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic biotoxins produced by marine algae that can accumulate in shellfish and cause the human illness known as diarrhetic shellfish poisoning (DSP). Regulatory testing of shellfish is required to protect consumers and the seafood industry. Certified reference materials (CRMs) are essential for the development, validation, and quality control of analytical methods, and thus play an important role in toxin monitoring. This paper summarizes work on research and development of shellfish tissue reference materials for OA and DTXs. Preliminary work established the appropriate conditions for production of shellfish tissue CRMs for OA and DTXs. Source materials, including naturally incurred shellfish tissue and cultured algae, were screened for their DSP toxins. This preliminary work informed planning and production of a wet mussel (Mytilus edulis) tissue homogenate matrix CRM. The homogeneity and stability of the CRM were evaluated and found to be fit-for-purpose. Extraction and LC-tandem MS methods were developed to accurately certify the concentrations of OA, DTX1, and DTX2 using a combination of standard addition and matrix-matched calibration to compensate for matrix effects in electrospray ionization. The concentration of domoic acid was also certified. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization. The presence of other toxins in the CRM was also assessed and information values are reported for OA and DTX acyl esters.

  15. A fundamental discussion of what triggers localized deformation in geological materials

    NASA Astrophysics Data System (ADS)

    Peters, Max; Paesold, Martin; Poulet, Thomas; Herwegh, Marco; Regenauer-Lieb, Klaus; Veveakis, Manolis

    2015-04-01

    critical amount of dissipative work translated into heat over the diffusive capacity of the system by an instability study designed for such materials (Gruntfest, 1963). With respect to our numerical experiments, this critical parameter determines the timing when the entire amount of deformation energy translated into heat cannot be diffusively transported out of the system anymore. The resulting local temperature rise then induces strain localization. In contrast to classical shear heating scenarios with (catastrophic) thermal runaways, temperature variations of less than 1 K are sufficient for this localization mode to occur due to the balance between heat producing (e.g. dislocation creep) and consuming (grain growth) processes in the present setup. We demonstrate that this rise in latent heat is sufficient to provoke grain growth, operating as an endothermic reaction, stabilizing the simulated localized structure in turn. Various localized ductile structures, such as folded or boudinaged layers, can therefore be placed at the same material failure mode due to fundamental energy bifurcations triggered by dissipative work out of homogeneous state. Finally, we will discuss situations, in which structural heterogeneities are considered negligible and where the energy theory described here plays an underlying role by means of a comparison between numerical experiments and natural examples. REFERENCES Austin, N. and Evans, B. (2007). Paleowattmeters: A scaling relation for dynamically recrystallized grain size. Geology, 35. Gruntfest, I.J. (1963). Thermal feedback in liquid flow, plane shear at constant stress. Transactions of the Society of Rheology, 7. Hansen, L.N. and Zimmermann, M.E. and Dillman, A.M. and Kohlstedt, D.L (2012). Strain localization in olivine aggregates at high temperature: a laboratory comparison of constant-strain-rate and constant-stress boundary conditions. Earth and Planetary Science Letters, 333-334. Herwegh, M., Poulet, T., Karrech, A. and

  16. Research by the U.S. Geological Survey on organic materials in water

    USGS Publications Warehouse

    Baker, Robert Andrew

    1976-01-01

    The U.S. Geological Survey has responsibility for investigating the Nation's water resources for source, availability, quantity, and quality. This paper describes the Geological Survey's research on organic substances in water and fluvial sediments. Results and ongoing studies are examined. Typical research includes: Separation, concentration, and chromatographic identification of volatile acids; free-flow electrophoresis fractionation of natural organic materials; identification of chlorinated insecticides in suspended sediments and bottom materials; fate of organics following underground disposal; determination of humic and fulvic acid stability constants and characterizations; identification of low-molecular weight chloroorganic constituents in water; PCB (polychlorinated biphenyl compound) distribution in aquatic environments; dissolved organic carbon in ground water; and improvement in separation and concentration schemes prior to analyses.

  17. Multielement analysis of geologic materials by inductively coupled plasma-atomic emission spectroscopy

    SciTech Connect

    Christensen, O.D.; Kroneman, R.L.; Capuano, R.M.

    1980-03-01

    Atomic emission spectroscopy using an inductively coupled plasma (ICP) source permits the rapid acquisition of multielement geochemical data from a wide variety of geologic materials. Rocks or other solid samples are taken into solution with a four acid digestion procedure and introduced directly into the plasma; fluid samples are acidified or analyzed directly. The entire process is computer-controlled, fully-automated, and requires less than five minutes per sample for quantitative determination of 37 elements. The procedures and instrumentation employed at the ESL for multielement ICP analysis of geologic materials are described and these are intended as a guide for evaluating analytic results reported from this laboratory. The quality of geochemical data can be characterized by precision, limits of quantitative determination, and accuracy. Precision values are a measure of the repeatability of analyses. In general, major element and analyses have precision of better than 5% and trace elements of better than 10% of the amount present. (MHR)

  18. Geologic setting of diverse volcanic materials in northern Elysium Planitia, Mars

    NASA Technical Reports Server (NTRS)

    Mouginis-Mark, P. J.

    1990-01-01

    Geologic mapping of high-resolution (30-50 m/pixel) Viking Orbiter images of northern Elysium Planitia has identified seven sites where current problems in martian volcanology, chronology, and stratigraphy can be resolved. These sites, which are discussed in the context of a potential Mars rover/sample return mission, would permit the following investigations: (1) the dating of Lower Amazonian lava flows from Elysium Mons (thereby providing absolute calibration for global crater size/frequency relative chronologies, (2) the petrologic investigation of long run-out lava flows, (3) the geologic interpretation of materials that may either be lava flows or lahar deposits, (4) the analysis of materials believed to be ash deposits produced by explosive eruptions of Hecates Tholus, and (5) the investigation of the stratigraphy of fractured terrain along the boundary between northern Elysium Planitia and southern Utopia Planitia.

  19. Acquisition of improved reference values for cesium, iodine, strontium, thorium, and uranium in selected NIST reference materials.

    PubMed

    Parr, R M; Kawamura, H; Iyengar, G V

    1999-01-01

    As part of a study on the ingestion and organ content of some trace elements of importance in radiological protection, additional work has been undertaken to acquire improved reference values for cesium, iodine, strontium, thorium, and uranium in four selected reference materials provided by the US National Institute of Standards and Technology. The materials are SRM-1548 Total Diet, SRM-1548a Typical Diet, SRM-1486 Bone Meal, and RM-8414 Bovine Muscle. A coordinated study was undertaken with the help of seven selected laboratories in five countries. Instrumental and radiochemical neutron activation analysis and inductively coupled plasma-mass spectrometry were the analytical main techniques used.

  20. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 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...

  1. A Bibliography of Reference Materials for Evaluating Foreign Student Credentials.

    ERIC Educational Resources Information Center

    Hefling, Robert, Ed.

    The Academic Advisory Staff (AAS) of the Office of International Training (OIT), Agency for International Development (AID) analyzes and interprets the academic credentials of AID participants from cooperating countries in terms of the educational system of the U. S. To carry out this service the AAS has developed a library of reference materials…

  2. Dynamic simulations of geologic materials using combined FEM/DEM/SPH analysis

    SciTech Connect

    Morris, J P; Johnson, S M

    2008-03-26

    An overview of the Lawrence Discrete Element Code (LDEC) is presented, and results from a study investigating the effect of explosive and impact loading on geologic materials using the Livermore Distinct Element Code (LDEC) are detailed. LDEC was initially developed to simulate tunnels and other structures in jointed rock masses using large numbers of polyhedral blocks. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model this class of problems, LDEC now includes implementations of Cosserat point theory and cohesive elements. This approach directly simulates the transition from continuum to discontinuum behavior, thereby allowing for dynamic fracture within a combined finite element/discrete element framework. In addition, there are many application involving geologic materials where fluid-structure interaction is important. To facilitate solution of this class of problems a Smooth Particle Hydrodynamics (SPH) capability has been incorporated into LDEC to simulate fully coupled systems involving geologic materials and a saturating fluid. We will present results from a study of a broad range of geomechanical problems that exercise the various components of LDEC in isolation and in tandem.

  3. Atomic-absorption spectrochemical analysis for ultratrace elements in geological materials by hydride-forming techniques: Selenium.

    PubMed

    Sighinolfi, G P; Gorgoni, C

    1981-03-01

    A method based on hydride generation for the AAS determination of selenium at nanogram levels in geological materials is described. The sample is decomposed by aqua regia attack in a sealed Teflon bomb. After treatment with hydrochloric acid, selenium is converted into hydrogen selenide by reaction with sodium borohydride and determined by AAS. Matrix interference effects have been investigated, but though they are rarely significant, the standard-additions method is recommended. The absolute sensitivity of the method is about 2.0 ng of Se (in 10 ml of solution). Detection limits of about 5-10 ng in a 1.0-g sample have been achieved with the use of "Suprapure" reagents. The selenium content of some USGS, CRPG and ANRT reference samples is reported.

  4. 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.

  5. Homogeneity of the geochemical reference material BRP-1 (paraná basin basalt) and assessment of minimum mass

    USGS Publications Warehouse

    Cotta, Aloisio J. B.; Enzweiler, Jacinta; Wilson, Stephen A.; Perez, Carlos A.; Nardy, Antonio J. R.; Larizzatti, Joao H.

    2007-01-01

    Reference materials (RM) are required for quantitative analyses and their successful use is associated with the degree of homogeneity, and the traceability and confidence limits of the values established by characterisation. During the production of a RM, the chemical characterisation can only commence after it has been demonstrated that the material has the required level of homogeneity. Here we describe the preparation of BRP-1, a proposed geochemical reference material, and the results of the tests to evaluate its degree of homogeneity between and within bottles. BRP-1 is the first of two geochemical RM being produced by Brazilian institutions in collaboration with the United States Geological Survey (USGS) and the International Association of Geoanalysts (IAG). Two test portions of twenty bottles of BRP-1 were analysed by wavelength dispersive-XRF spectrometry and major, minor and eighteen trace elements were determined. The results show that for most of the investigated elements, the units of BRP-1 were homogeneous at conditions approximately three times more rigorous than those strived for by the test of “sufficient homogeneity”. Furthermore, the within bottle homogeneity of BRP-1 was evaluated using small beam (1 mm2) synchrotron radiation XRF spectrometry and, for comparison, the USGS reference materials BCR-2 and GSP-2 were also evaluated. From our data, it has been possible to assign representative minimum masses for some major constituents (1 mg) and for some trace elements (1-13 mg), except Zr in GSP-2, for which test portions of 74 mg are recommended.

  6. 10 CFR 431.303 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... by DOE. Material is incorporated as it exists on the date of the approval and a notice of any change...) NFRC. National Fenestration Rating Council, 6305 Ivy Lane, Ste. 140, Greenbelt, MD 20770, (301)...

  7. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the date of the approval and a notice of any change in the material will be published in the Federal.... Institute of Electrical and Electronics Engineers, Inc., 445 Hoes Lane, P.O. Box 1331, Piscataway, NJ...

  8. 10 CFR 431.303 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... by DOE. Material is incorporated as it exists on the date of the approval and a notice of any change...) NFRC. National Fenestration Rating Council, 6305 Ivy Lane, Ste. 140, Greenbelt, MD 20770, (301)...

  9. 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.

  10. 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.

  11. Conceptions of Geological Time among Primary Teacher Trainees, with Reference to Their Engagement with Geoscience, History, and Science.

    ERIC Educational Resources Information Center

    Trend, Roger

    2000-01-01

    Describes a study of preservice elementary teachers' (n=179) perceptions of geologic time. Finds that the respondents perceived events in Earth's geological past as falling into three distinct clusters: extremely ancient, less ancient, and geologically recent. Finds also that the teachers' grasp of relative time is more secure than their grasp of…

  12. Reference data for thermocouple materials below the ice point.

    NASA Technical Reports Server (NTRS)

    Sparks, L. L.; Powell, R. L.

    1972-01-01

    Standard thermoelectric data have been determined for four thermocouple combinations used below the ice point: commercial types E, K, and T and the special combination of KP vs Au-0.07 at.% Fe. Power series coefficients necessary to generate E = f(T) data for these combinations are given. In addition, extensive tests were carried out to ascertain the variability between materials from different manufacturers. Typical wires processed for low-temperature usage often have slightly thermoelectric properties (up to 1%) from those, nominally identical, wires made for high-temperature applications. Generally, type E is the most satisfactory standardized commercial combination. The Au-0.07 at.% Fe material has been examined in particular detail, because it is not yet an ISA standard material. It has excellent sensitivity in the liquid helium/liquid hydrogen temperature range and a nearly linear thermovoltage at higher temperatures.

  13. Determination of water in NIST reference material for mineral oils

    PubMed

    Cedergren; Nordmark

    2000-07-15

    The accuracy of the reference concentrations of moisture in electrical insulating oil RM 8506 and lubricating oil RM 8507 (both of mineral type) and specified by the National Institute of Standards and Technology (NIST) as containing 39.7 and 76.8 ppm (w/w) water, respectively, has recently been the subject of debate in this journal. To shed some further light on this controversy, we report in this correspondence results for these oils obtained by two additional methods, one based on specially designed reagents for diaphragm-free Karl Fischer (KF) coulometry and the other based on the concept of stripping at elevated temperature/continuous KF coulometry. A positive interference effect was shown to take place for RM 8506 when the direct coulometric method was used. If the results are corrected for this, the values including six different procedures varied in the range 13.5-15.6 ppm (w/w). For RM 8507, all values were between 42.5 and 47.2 ppm (w/w), which means that the values recommended by NIST for both reference oils using volumetric titration are about twice as high as those obtained with the other techniques. A possible explanation for this discrepancy is presented.

  14. 10 CFR 431.133 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... inspection at the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building....133 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL...://www1.eere.energy.gov/buildings/appliance_standards/. Also, this material is available for inspection...

  15. 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...

  16. 10 CFR 435.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 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... material is available for inspection at the U.S. Department of Energy, Office of Energy Efficiency...

  17. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND..., this material is available for inspection at U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza SW., Washington, DC...

  18. 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 CONSTRUCTION OF NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.3 Materials... organization will not affect the DOE building energy performance standard unless and until DOE amends...

  19. 10 CFR 435.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 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... material is available for inspection at the U.S. Department of Energy, Office of Energy Efficiency...

  20. 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...

  1. 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 CONSTRUCTION OF NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH-RISE RESIDENTIAL BUILDINGS § 433.3 Materials... organization will not affect the DOE building energy performance standard unless and until DOE amends...

  2. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ....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...

  3. 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...

  4. 10 CFR 435.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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... material is available for inspection at the U.S. Department of Energy, Office of Energy Efficiency...

  5. 10 CFR 430.3 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza, SW., Washington, DC 20024, (202... 51”), Food equipment materials, revised and adopted April 2007, IBR approved for § 430.2. (2) (o... Energy, Office of Energy Efficiency and Renewable Energy, Resource Room of the Building...

  6. 40 CFR 600.011-93 - Reference materials.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Natural Gas By Gas Chromatography, IBR approved for §§ 600.113-93, 600.113-08. (c) SAE Material. The... at http://www.sae.org. (1) Motor Vehicle Dimensions—Recommended Practice SAE 1100a (Report of...

  7. 10 CFR 431.443 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the date of the approval and a notice of any change in the material will be published in the Federal... §§ 431.444; 431.447. (c) IEEE. Institute of Electrical and Electronics Engineers, Inc., 445 Hoes Lane,...

  8. 15 CFR 200.104 - Standard reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE MEASUREMENT SERVICES POLICIES, SERVICES... the NIST National Measurement Laboratory administers a program to provide many types of well-characterized materials that are needed to calibrate a measurement system or to produce scientific data that...

  9. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 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) Standard 727-1994, “Standard for Safety Oil-Fired Central Furnaces,” IBR approved for § 431.76. (3) Sections...

  10. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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) Standard 727-1994, “Standard for Safety Oil-Fired Central Furnaces,” IBR approved for § 431.76. (3) Sections...

  11. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 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) Standard 727-1994, “Standard for Safety Oil-Fired Central Furnaces,” IBR approved for § 431.76. (3) Sections...

  12. 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…

  13. 40 CFR 600.011-93 - Reference materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... ASTM D 1945-91 Standard Test Method for Analysis of Natural Gas By Gas Chromatography. 600.113-93, 600... Natural Gas By Gas Chromatography, IBR approved for §§ 600.113-93, 600.113-08. (c) SAE Material....

  14. 10 CFR 431.15 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Part 12, Tests and Performance—AC and DC Motors: (A) Paragraphs 12.35.1, 12.35.2, 12.38.1, 12.38.2, 12... INDUSTRIAL EQUIPMENT Electric Motors Test Procedures, Materials Incorporated and Methods of Determining... Floor, 950 L'Enfant Plaza SW., Washington, DC 20024, (202) 586-2945, or go to...

  15. Reference Materials--So Many Choices, So Little Money: Librarians and Publishers Speak Out!

    ERIC Educational Resources Information Center

    Wilkinson, Frances C.

    1997-01-01

    Differing perspectives of reference collection development librarians and publishers are presented for the following topics: fairness of pricing trends; best/worst ways to communicate about new reference titles; deciding which sources should be published; impact of electronic materials on reference services; deciding on/selecting formats; and…

  16. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INDUSTRIAL EQUIPMENT Commercial Warm Air Furnaces Test Procedures § 431.75 Materials incorporated by... Z21.47-1998”), “Gas-Fired Central Furnaces,” approved by ANSI on June 9, 1998, IBR approved for § 431.76. (2) ANSI Z21.47-2006, (“ANSI Z21.47-2006”), “Gas-Fired Central Furnaces,” approved on July...

  17. 10 CFR 431.75 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INDUSTRIAL EQUIPMENT Commercial Warm Air Furnaces Test Procedures § 431.75 Materials incorporated by... Z21.47-1998”), “Gas-Fired Central Furnaces,” approved by ANSI on June 9, 1998, IBR approved for § 431.76. (2) ANSI Z21.47-2006, (“ANSI Z21.47-2006”), “Gas-Fired Central Furnaces,” approved on July...

  18. 10 CFR 431.15 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Performance—AC and DC Motors: (A) Paragraphs 12.35.1, 12.35.2, 12.38.1, 12.38.2, 12.39.1, 12.39.2, and 12.40.1... INDUSTRIAL EQUIPMENT Electric Motors Test Procedures, Materials Incorporated and Methods of Determining..., DC 20024, (202) 586-2945, or go to http://www1.eere.energy.gov/buildings/appliance_standards/....

  19. Multispectral Microscopic Imager (MMI): Multispectral Imaging of Geological Materials at a Handlens Scale

    NASA Astrophysics Data System (ADS)

    Farmer, J. D.; Nunez, J. I.; Sellar, R. G.; Gardner, P. B.; Manatt, K. S.; Dingizian, A.; Dudik, M. J.; McDonnell, G.; Le, T.; Thomas, J. A.; Chu, K.

    2011-12-01

    The Multispectral Microscopic Imager (MMI) is a prototype instrument presently under development for future astrobiological missions to Mars. The MMI is designed to be a arm-mounted rover instrument for use in characterizing the microtexture and mineralogy of materials along geological traverses [1,2,3]. Such geological information is regarded as essential for interpreting petrogenesis and geological history, and when acquired in near real-time, can support hypothesis-driven exploration and optimize science return. Correlated microtexure and mineralogy also provides essential data for selecting samples for analysis with onboard lab instruments, and for prioritizing samples for potential Earth return. The MMI design employs multispectral light-emitting diodes (LEDs) and an uncooled focal plane array to achieve the low-mass (<1kg), low-cost, and high reliability (no moving parts) required for an arm-mounted instrument on a planetary rover [2,3]. The MMI acquires multispectral, reflectance images at 62 μm/pixel, in which each image pixel is comprised of a 21-band VNIR spectrum (0.46 to 1.73 μm). This capability enables the MMI to discriminate and resolve the spatial distribution of minerals and textures at the microscale [2, 3]. By extending the spectral range into the infrared, and increasing the number of spectral bands, the MMI exceeds the capabilities of current microimagers, including the MER Microscopic Imager (MI); 4, the Phoenix mission Robotic Arm Camera (RAC; 5) and the Mars Science Laboratory's Mars Hand Lens Imager (MAHLI; 6). In this report we will review the capabilities of the MMI by highlighting recent lab and field applications, including: 1) glove box deployments in the Astromaterials lab at Johnson Space Center to analyze Apollo lunar samples; 2) GeoLab glove box deployments during the 2011 Desert RATS field trials in northern AZ to characterize analog materials collected by astronauts during simulated EVAs; 3) field deployments on Mauna Kea

  20. [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.

  1. Basic petroleum geology, 2nd ed. , revised

    SciTech Connect

    Link.

    1990-01-01

    This book contains revised and updated material, including approximately 200 additional illustrations and an extensive glossary of terms. A valuable reference for geology students and petroleum professionals, the text presents fundamental concepts of geology in terms of sedimentary deposition, petroleum occurrence, exploration, and recovery. This book contains information on geologic time, historical geology and stratigraphy; Minerals and rocks; Weathering erosion, and deposition; Marine erosion and deposition; Depositional basins; Lacustrine, desert and glacial environments; Subsurface water and diagenesis; Structural geology; petroleum traps; Petroleum and reservoirs; Geological considerations and engineering practices; Rocks, reservoirs, and recovery techniques; Exploration techniques for petroleum; Bibliography Glossary; Index.

  2. 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.

  3. 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.

  4. 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

  5. Simplified method for the determination of Ru, Pd, Re, Os, Ir and Pt in chromitites and other geological materials by isotope dilution ICP-MS and acid digestion.

    PubMed

    Meisel, T; Moser, J; Fellner, N; Wegscheider, W; Schoenberg, R

    2001-03-01

    A method for the determination of low Ru, Pd, Re, Os, Ir and Pt abundances in geological reference materials by isotope dilution inductively coupled plasma mass spectrometry (ICP-MS) after acid digestion in a high pressure asher (HPA-S) is presented. The digestion technique is similar to that using Carius tubes but easier to handle and reaches higher temperatures. Osmium can be determined as OsO4 with ICP-MS directly after digestion through a sparging technique. The remaining elements are preconcentrated by means of anion column chromatography. The resin is digested directly without elution leading to high yields but this causes problems if Zr is present at higher levels in the silicate rich materials. The analytical results for international platinum group element (PGE) reference materials, chromitite CHR-Bkg, basalt TDB-1 and gabbro WGB-1, are presented and compared with literature data, demonstrating the validity of the described method. Although higher in concentration, PGEs determined for reference material WGB-1 were worse than for TDB-1 indicating a more inhomogeneous distribution of the platinum group mineral phases. The low PGE abundance chromitite standard, CHR-Bkg, is likely to be homogeneous for Ru, Re, Os and Ir and is recommended as a reference material for the study of chromitites. Detection limits (3s x total procedure blank) range from 0.012 ng (Re and Os) to 0.77 ng (Pt), which could be further improved by applying higher quality acids.

  6. 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.

  7. Reference Materials for Secondary School Library Media Centers. Library Resources #2 [and] Selected Bibliography of Elementary Reference Materials. Library Resources #25.

    ERIC Educational Resources Information Center

    Estes, Bettie

    These two annotated bibliographies list reference materials for the secondary school and elementary school levels. Each bibliography contains entries arranged alphabetically by title under Dewey Decimal Classification headings, i.e., 000s through 900s. Entries consist of the title, author/published, publication date, and cost; elementary-level…

  8. Atomic absorption spectrometric determination of copper, zinc, and lead in geological materials

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1976-01-01

    An atomic absorption spectrometric method is described for the determination of copper, zinc, and lead in geological materials. The sample is digested with HF-HCl-H2O2; the final solution for analysis is in 10 % (v/v) HCl. Copper and zinc are determined directly by aspirating the solution into an air-acetylene flame. A separate aliquot of the solution is used for determination of lead; lead is extracted into TOPO-MIBK from the acidic solution in the presence of iodide and ascorbic acid. For a 0.50-g sample, the limits of determination are 10-2000 p.p.m. for Cu and Zn, and 5-5000 p.p.m. for Pb. As much as 40 % Fe or Ca. and 10 % Al, Mg, or Mn in the sample do not interfere. The proposed method can be applied to the determination of copper, zinc, and lead in a wide range of geological materials including iron- and manganese-rich, calcareous and carbonate samples. ?? 1976.

  9. 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

  10. 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...

  11. 43 CFR 10010.33 - Incorporation by reference of material into NEPA documents.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... IMPLEMENTING THE NATIONAL ENVIRONMENTAL POLICY ACT Environmental Impact Statements § 10010.33 Incorporation by reference of material into NEPA documents. Citations of specific topics will include the pertinent...

  12. 43 CFR 10010.33 - Incorporation by reference of material into NEPA documents.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... IMPLEMENTING THE NATIONAL ENVIRONMENTAL POLICY ACT Environmental Impact Statements § 10010.33 Incorporation by reference of material into NEPA documents. Citations of specific topics will include the pertinent...

  13. 43 CFR 10010.33 - Incorporation by reference of material into NEPA documents.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... IMPLEMENTING THE NATIONAL ENVIRONMENTAL POLICY ACT Environmental Impact Statements § 10010.33 Incorporation by reference of material into NEPA documents. Citations of specific topics will include the pertinent...

  14. 43 CFR 10010.33 - Incorporation by reference of material into NEPA documents.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... IMPLEMENTING THE NATIONAL ENVIRONMENTAL POLICY ACT Environmental Impact Statements § 10010.33 Incorporation by reference of material into NEPA documents. Citations of specific topics will include the pertinent...

  15. Certification of elements in and use of standard reference material 3280 multivitamin/multielement tablets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Standard Reference Material (SRM) 3280 Multivitamin/Multielement Tablets was issued by the National Institute of Standards and Technology (NIST) in 2009 and has certified and reference mass fraction values for 13 vitamins, 26 elements, and 2 carotenoids. Elements were measured using two or more ana...

  16. 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…

  17. Requirements for the Development of Bacillus Anthracis Spore Reference Materials Used to Test Detection Systems

    PubMed Central

    Almeida, Jamie L.; Wang, Lili; Morrow, Jayne B.; Cole, Kenneth D.

    2006-01-01

    Bacillus anthracis spores have been used as biological weapons and the possibility of their further use requires surveillance systems that can accurately and reliably detect their presence in the environment. These systems must collect samples from a variety of matrices, process the samples, and detect the spores. The processing of the sample may include removal of inhibitors, concentration of the target, and extraction of the target in a form suitable for detection. Suitable reference materials will allow the testing of each of these steps to determine the sensitivity and specificity of the detection systems. The development of uniform and well-characterized reference materials will allow the comparison of different devices and technologies as well as assure the continued performance of detection systems. This paper discusses the special requirements of reference materials for Bacillus anthracis spores that could be used for testing detection systems. The detection of Bacillus anthracis spores is based on recognition of specific characteristics (markers) on either the spore surface or in the nucleic acids (DNA). We have reviewed the specific markers and their relevance to characterization of reference materials. We have also included the approach for the characterization of candidate reference materials that we are developing at the NIST laboratories. Additional applications of spore reference materials would include testing sporicidal treatments, techniques for sampling the environment, and remediation of spore-contaminated environments. PMID:27274929

  18. 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

  19. Atomic-absorption determination of beryllium in geological materials by use of electrothermal atomization

    USGS Publications Warehouse

    Campbell, E.Y.; Simon, F.O.

    1978-01-01

    A method is described for the atomic-absorption determination of beryllium in geological materials, that utilizes electrothermal atomization after a separation by solvent extraction. Samples are decomposed with hydrofluoric acid and nitric acid in Teflon-lined pressure decomposition vessels. Beryllium is isolated by its extraction as beryllium acetylacetonate at pH 8 into xylene and back-extraction in 3M hydrochloric acid. The method has been successfully applied to the determination of beryllium in 14 U.S. Geological Survey standard rocks. Four subsamples from four bottles of each standard sample were analysed in random order. The mean beryllium contents (ppm) are: AGV-1, 1.98; PCC-1, 0.024; MAG-1, 2.84; BHVO-1, 0.90; DTS-1, 0.026; SCo-1, 1.74; SDC-1, 2.52; BCR-1, 1.44; GSP-1, 1.22; SGR-1, 0.86; QLO-1, 1.83; RGM-1, 2.21; STM-1, 8.75; G-2, 2.29. An analysis of variance shows that all the samples may be considered homogeneous at F0.95 except AGV-1 and DTS-1 which may be considered homogeneous at F0.99. ?? 1978.

  20. 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.

  1. Certification of elements in and use of standard reference material 3280 multivitamin/multielement tablets.

    PubMed

    Turk, Gregory C; Sharpless, Katherine E; Cleveland, Danielle; Jongsma, Candice; Mackey, Elizabeth A; Marlow, Anthony F; Oflaz, Rabia; Paul, Rick L; Sieber, John R; Thompson, Robert Q; Wood, Laura J; Yu, Lee L; Zeisler, Rolf; Wise, Stephen A; Yen, James H; Christopher, Steven J; Day, Russell D; Long, Stephen E; Greene, Ella; Harnly, James; Ho, I-Pin; Betz, Joseph M

    2013-01-01

    Standard Reference Material 3280 Multivitamin/ Multielement Tablets was issued by the National Institute of Standards and Technology in 2009, and has certified and reference mass fraction values for 13 vitamins, 26 elements, and two carotenoids. Elements were measured using two or more analytical methods at NIST with additional data contributed by collaborating laboratories. This reference material is expected to serve a dual purpose: to provide quality assurance in support of a database of dietary supplement products and to provide a means for analysts, dietary supplement manufacturers, and researchers to assess the appropriateness and validity of their analytical methods and the accuracy of their results.

  2. Geological gyrocompass

    NASA Astrophysics Data System (ADS)

    McKeown, M. H.; Beason, S. C.

    1988-08-01

    The geological gyrocompass is an accurate, portable instrument useful for geologic mapping and surveying which employs an aircraft gyrocompass, strike reference bars, a pair of sights and levelling devices for horizontally levelling the instrument. A clinometer graduated in degrees indicates the dip of the surface being measured.

  3. An atomic-absorption method for the determination of gold in large samples of geologic materials

    USGS Publications Warehouse

    VanSickle, Gordon H.; Lakin, Hubert William

    1968-01-01

    A laboratory method for the determination of gold in large (100-gram) samples has been developed for use in the study of the gold content of placer deposits and of trace amounts of gold in other geologic materials. In this method the sample is digested with bromine and ethyl ether, the gold is extracted into methyl isobutyl ketone, and the determination is made by atomicabsorption spectrophotometry. The lower limit of detection is 0.005 part per million in the sample. The few data obtained so far by this method agree favorably with those obtained by assay and by other atomic-absorption methods. About 25 determinations can be made per man-day.

  4. Determination of gold in geologic materials by solvent extraction and atomic-absorption spectrometry

    USGS Publications Warehouse

    Huffman, Claude; Mensik, J.D.; Riley, L.B.

    1967-01-01

    The two methods presented for the determination of traces of gold in geologic materials are the cyanide atomic-absorption method and the fire-assay atomic-absorption method. In the cyanide method gold is leached with a sodium-cyanide solution. The monovalent gold is then oxidized to the trivalent state and concentrated by extracting into methyl isobutyl ketone prior to estimation by atomic absorption. In the fire-assay atomic-absorption method, the gold-silver bead obtained from fire assay is dissolved in nitric and hydrochloric acids. Gold is then concentrated by extracting into methyl isobutyl ketone prior to determination by atomic absorption. By either method concentrations as low as 50 parts per billion of gold can be determined in a 15-gram sample.

  5. Geologic and hydrologic features of the San Bernardino area, California - with special reference to underflow across the San Jacinto fault

    USGS Publications Warehouse

    Dutcher, L.C.; Garrett, Arthur A.

    1963-01-01

    This is the second in a series of interpretive reports on subsurface outflow from the ground-water basins of San Bernardino County, Calif., prepared by the U.S. Geological Survey in cooperation with the San Bernardino County Flood Control District. One principal purpose of the study was to estimate the ground-water outflow from the Bunker Hill basin to the Rialto-Colton basin across the San Jacinto fault, which, except locally, forms a nearly impermeable boundary between the two basins. In addition, the report deals qualitatively with the geology, the fault barriers that divide the area into several ground-water basins, the physical nature and degree of imperviousness of the barriers, the occurrence and movement of ground water and fluctuations of water level in the basins, and the chemical quality of surface and ground waters in the San Bernardino area. The report includes a geologic map and sections, water-level-contour maps and profiles, and hydrographs of selected well. The Santa Ana River, the principal stream, flows generally westward across the area. Channels of the river and its tributaries overlie a large irregular structural depression filled with alluvial deposits ranging in age from late Tertiary to Recent and forming a valley bounded on the north by the San Gabriel Mountains, on the east by the San Bernardino Mountains, and on the south by an irregular group of hills. Large alluvial fans underlie most of the area, but its landforms also include alluvial benches and terraces near the mountains, stream channels, and elongate hills, ridges, and scarps along the trace of the San Jacinto fault, which strikes northwestward across the valley about in the center of the area. This fault and others divide the area into ground-water basins, which include the Bunker Hill, Rialto-Colton, upper and lower Lytle and Chino basins. The water-bearing deposits include the following units: the younger alluvium. of Recent age, which occupies principally the backfilled

  6. 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 ...

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .../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 § 1068.95—SAE Materials Document number and name Part 1068reference SAE J1930, Electrical/Electronic Systems...

  8. 40 CFR 1068.95 - What materials does this part reference?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .../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 § 1068.95—SAE Materials Document number and name Part 1068reference SAE J1930, Electrical/Electronic Systems...

  9. 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 ...

  10. Determination of rare earth elements in geological materials by inductively coupled argon plasma/atomic emission spectrometry

    USGS Publications Warehouse

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    Inductively coupled argon plasma/optical emission spectrometery (ICAP/OES) is useful as a simultaneous, multielement analytical technique for the determination of trace elements in geological materials. A method for the determination of trace-level rare earth elements (REE) in geological materials using an ICAP 63-channel emission spectrometer is described. Separation and preconcentration of the REE and yttrium from a sample digest are achieved by a nitric acid gradient cation exchange and hydrochloric acid anion exchange. Precision of 1-4% relative standard deviation and comparable accuracy are demonstrated by the triplicate analysis of three splits of BCR-1 and BHVO-1. Analyses of other geological materials including coals, soils, and rocks show comparable precision and accuracy.

  11. Using U.S. Geological Survey data in material flow analysis: An introduction

    USGS Publications Warehouse

    Sibley, S.F.

    2009-01-01

    A few sources of basic data on worldwide raw materials production and consumption exist that are independently developed and freely available to the public. This column is an introduction to the types of information available from the U.S. Geological Survey (USGS), and explains how the data are assembled. The kind of information prepared by the USGS is essential to U.S. materials flow studies because the data make it possible to conduct these studies within a global context. The data include primary and secondary (scrap) production, consumption and stocks (mostly limited to the United States unless calculated), trade (not readily available for all countries), and prices for more than 80 mineral commodities. Materials flow studies by USGS specialists using these data are continuing (http://minerals.usgs.gov/minerals/mflow/). Figure 1 shows from where the data are collected and where they are used. Minerals information was downloaded by users 5.8 million times from USGS minerals information Web pages in 2008.

  12. U.S. Geological Survey Field Leach Test for Assessing Water Reactivity and Leaching Potential of Mine Wastes, Soils, and Other Geologic and Environmental Materials

    USGS Publications Warehouse

    Hageman, Philip L.

    2007-01-01

    The U. S. Geological Survey (USGS) has developed a fast (5-minute), effective, simple, and cost-effective leach test that can be used to simulate the reactions that occur when materials are leached by water. The USGS Field Leach Test has been used to predict, assess, and characterize the geochemical interactions between water and a broad variety of geologic and environmental matrices. Examples of some of the samples leached include metal mine wastes, various types of dusts, biosolids (processed sewage sludge), flood and wetland sediments, volcanic ash, forest-fire burned soils, and many other diverse matrices. The Field Leach Test has been an integral part of these investigations and has demonstrated its value as a geochemical characterization tool. It has enabled investigators to identify which constituents are water reactive, soluble, mobilized, and made bioaccessible because of leaching by water, and to understand potential impacts of these interactions on the surrounding environment.

  13. Analysis of biological reference materials, prepared by microwave dissolution, using inductively coupled plasma mass spectrometry.

    PubMed

    Friel, J K; Skinner, C S; Jackson, S E; Longerich, H P

    1990-03-01

    A procedure has been developed for the analysis of biological materials by inductively coupled plasma mass spectrometry (ICP-MS). Fast, efficient and complete sample digestion is achieved by a combined microwave-nitric acid/open beaker-nitric acid-hydrogen peroxide procedure. The ICP-MS analysis is performed with an on-line five-element internal standard to correct for matrix and instrumental drift effects. Results are presented for 24 elements in three biological reference materials (National Institute of Standards and Technology Standard Reference Materials 5277a Liver and 1566 Oyster and International Atomic Energy Agency Certified Reference Material H4 Animal Muscle). For all elements significantly above the detection limit and reagent blank concentrations, good agreement exists between ICP-MS and certified values.

  14. IAEA-447: a new certified reference material for environmental radioactivity measurements.

    PubMed

    Shakhashiro, A; Tarjan, S; Ceccatelli, A; Kis-Benedek, G; Betti, M

    2012-08-01

    The environment program of the International Atomic Energy Agency (IAEA) includes activities to produce and certify reference materials for environmental radioactivity measurements. This paper describes methodologies applied in preparation and certification of the new IAEA-447 moss-soil certified reference material. In this work, the massic activities and associated standard uncertainties of (40)K, (90)Sr, (137)Cs, (208)Tl, (210)Pb, (210)Po, (212)Pb, (214)Pb, (214)Bi, (226)Ra, (228)Ac, (234)Th, (234)U, (238)U, (238)Pu, (239+240)Pu, (241)Pu and (241)Am were established. Details of the analytical methods including radiochemical procedures were reported. Analytical challenges and lessons learned from the reported results in the worldwide IAEA proficiency test using this material was summarized and best analytical practices to improve the performance for environmental radioactivity determinations were recommended. IAEA-447 is an important reference material for quality control and method validation of gamma-ray spectrometry and radiochemical analytical procedures.

  15. Determination of sub-microgram amounts of selenium in geological materials by atomic-absorption spectrophotometry with electrothermal atomisation after solvent extraction

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1981-01-01

    An atomic-absorption spectrophotometric method with electrothermal atomisation has been developed for the determination of selenium in geological materials. The sample is decomposed with a mixture of nitric, perchloric and hydrofluoric acids and heated with hydrochloric acid to reduce selenium to selenium (IV). Selenium is then extracted into toluene from a hydrochloric acid - hydrobromic acid medium containing iron. A few microlitres of the toluene extract are injected into a carbon rod atomiser, using a nickel solution as a matrix modifier. The limits of determination are 0.2-200 p.p.m. of selenium in a geological sample. For concentrations between 0.05 and 0.2 p.p.m., back-extraction of the selenium into dilute hydrochloric acid is employed before atomisation. Selenium values for reference samples obtained by replicate analysis are in general agreement with those reported by other workers, with relative standard deviations ranging from 4.1 to 8.8%. Recoveries of selenium spiked at two levels were 98-108%. Major and trace elements commonly encountered in geological materials do not interfere. Arsenic has a suppressing effect on the selenium signals, but only when its concentration is greater than 1000 p.p.m. Nitric acid interferes seriously with the extraction of selenium and must be removed by evaporation in the sample-digestion step.

  16. Water resources of southeastern Florida, with special reference to geology and ground water of the Miami area

    USGS Publications Warehouse

    Parker, Garald G.; Ferguson, G.E.; Love, S.K.

    1955-01-01

    The circulation of water, in any form, from the surface of the earth to the atmosphere and back again is called the hydrologic cycle. A comprehensive study of the water resources of any area must, therefore, include data on the climate of the area. The humid subtropical climate of southeast Florida is characterized by relatively high temperatures, alternating semi-annual wet and dry season, and usually light put persistent winds. The recurrence of drought in an area having relatively large rainfall such as southeastern Florida indicates that the agencies that remove water are especially effective. Two of the most important of the agencies associated with climate are evaporation and transpiration, or 'evapotranspiraton'. Evaporation losses from permanent water areas are believed to average between 40 and 45 inches per year. Over land areas indirect methods much be used to determine losses by evapotranspiration; necessarily, there values are not precise. Because of their importance in the occurrence and movement of both surface and ground waters, detailed studies were made of the geology and geomorphology of southern Florida. As a result of widespread crustal movements, southern Florida emerged from the sea in later Pliocene time and probably was slightly tilted to the west. At the beginning of the Pleistocene the continent emerged still farther as a result of the lowering of sea level attending the first widespread glaciation. During this epoch, south Florida may have stood several hundred feet above sea level. During the interglacial ages the sea repeatedly flooded southern Florida. The marine members of the Fort Thompson formation in the Lake Okeechobee-Everglades depression and the Calossahatchee River Valley apparently are the deposits of the interglacial invasions by the sea. The fresh-water marls, sands, and organic deposits of the Fort Thompson formation appear to have accumulated during glacial ages when seas level was low and the area was a land surface

  17. A study of production of radioactive environmental reference materials used for proficiency testing program in Taiwan.

    PubMed

    Peng, En-Chi; Wang, Jeng-Jong

    2013-11-01

    To realise radioactive environmental reference materials in Taiwan, seven environmental materials of soil, water, vegetation, meat, airborne particles (filter paper), milk and mushroom samples that are frequently encountered were used to establish the preparation of the reference materials. These seven environmental materials were collected, checked for freedom from radioactivity and prepared according to their properties. The preparation was carried out by using activity about 10-100 times that of the minimum detectable activity (MDA) in routine measurements in the radioactive standard used to spike the inactive material and this standard is traceable to national ionising radioactivity standards (TAF, 2004). To demonstrate sample traceability to the added standard, each sample was carefully measured and its uncertainty evaluated. Based on the recommendations of ISO Guide 35 for evaluation of reference materials and with the above assessment and verification procedures, the uncertainties (k=1) of the spike activity used in making reference materials were: (60)Co≤4.6%, (134)Cs≤4.7%, (137)Cs≤5.0%, total β≤0.6% and (3)H≤1.3%.

  18. Fit-for-purpose shellfish reference materials for internal and external quality control in the analysis of phycotoxins.

    PubMed

    Hess, Philipp; McCarron, Pearse; Quilliam, Michael A

    2007-04-01

    The need for reference materials for quality control of analysis of foodstuffs has been stressed frequently. This has been particularly true in the phycotoxins field, where there is a great shortage of both pure calibration standards and reference materials. Worldwide there are very few independent bodies that produce certified reference materials for phycotoxins, the main producers currently being the National Research Council Canada and the Japanese Food Research Laboratory. Limited availability of contaminated shellfish and algae, as well as the time and knowledge necessary for the production of adequate reference materials, continuously lead to limited editions of certified reference materials and even more limited production of in-house reference materials. The restricted availability of in-house quality control materials promotes the rapid use of the limited certified reference materials, which in turn hampers the production of the suite of materials required globally for complete protection of public health. This paper outlines the various options that analysts can pursue in the use of reference materials for internal and external quality control, with a view to optimising the efforts of both reference materials users and reference materials producers. For this purpose, the logical sequence is reviewed from the discovery of a new bioactive compound in shellfish, through initial method development up to regulation for food safety purposes including accepted reference methods. Subsequently, the requirements for and efforts typically spent in the production and characterisation of laboratory reference materials, certified reference materials and other test materials used in inter-laboratory studies or proficiency testing, in the area of marine biotoxins are evaluated. Particular emphasis is put on practical advice for the preparation of in-house reference materials. The intricate link between reference material characterisation and method performance is

  19. 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.

  20. The calibration of XRF polyethylene reference materials with k0-NAA and ICP-AES

    NASA Astrophysics Data System (ADS)

    Swagten, Josefien; Bossus, Daniël; Vanwersch, Hanny

    2006-08-01

    Due to the lack of commercially available polyethylene reference materials for the calibration of X-ray fluorescence spectrometers (XRF), DSM Resolve, in cooperation with PANalytical, prepared and calibrated such a set of standards in 2005. The reference materials were prepared based on the addition of additives to virgin polyethylene. The mentioned additives are added to improve the performance of the polymers. The elements present in additives are tracers for the used additives. The reference materials contain the following elements: F, Na, Mg, Al, Si, P, S, Ca, Ti and Zn in the concentration range of 5 mg/kg for Ti, up to 600 mg/kg for Mg. The calibration of the reference materials, including a blank, was performed using inductively coupled plasma atomic emission spectrometry (ICP-AES) and Neutron Activation Analysis ( k0-NAA). ICP-AES was used to determine the elements Na, Mg, Al, P, Ca, Ti and Zn whereas k0-NAA was used for F, Na, Mg, Al, Ca, Ti and Zn. Over the complete concentration range, a good agreement of the results was found between the both techniques. This project has shown that within DSM Resolve, it is possible to develop and to calibrate homogenous reference materials for XRF.

  1. 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.

  2. The development and role of international biological reference materials in the diagnosis of anaemia.

    PubMed

    Thorpe, Susan J

    2010-07-01

    Anaemia is a major global health problem. Although the main cause is iron deficiency, anaemia also results from other nutritional deficiencies (folate and vitamin B12), haemolytic disorders including haemoglobinopathies, and bone marrow disorders. Accurate diagnosis of anaemia is dependent on reliable diagnostic tests and reference ranges, which in turn are dependent on effective standardisation. Standardisation is achieved through the availability of reference materials and reference measurement procedures. International biological reference materials have therefore been developed to standardise and control diagnostic tests for anaemia for a diverse range of analytes including total haemoglobin and haemoglobin types, ferritin, the serum transferrin receptor, serum vitamin B12 and folate, whole blood folate, and alloantibodies which mediate immune haemolytic anaemia.

  3. A Family of Reference Hugoniots for Two-phase Porous Materials

    DTIC Science & Technology

    2015-06-01

    UNCLASSIFIED UNCLASSIFIED A Family of Reference Hugoniots for Two-phase Porous Materials A.D. Resnyansky Weapons and Combat...of Australia 2015 AR-016-394 June 2015 APPROVED FOR PUBLIC RELEASE UNCLASSIFIED UNCLASSIFIED A Family of Reference Hugoniots for...EOS [4] is based on a constitutive consideration. The latter approach specifies Hugoniot states from a family of non-equilibrium Hugoniot for a

  4. Selected Bibliography on Culture and Cultural Materials, Preliminary Edition. Series A: Reference Materials, Human Relations in Cultural Context.

    ERIC Educational Resources Information Center

    Condon, E. C.; And Others

    Included in this bibliography are references to resources and materials available to the teacher and educator on human relations and cultural education. The bibliography is divided into three sections on culture, specific culture, and adult bilingual-bicultural education. The section on culture presents background information on the relation of…

  5. Matrix effects on the determination of manganese in geological materials by atomic-absorption spectrophotometry under different flame conditions

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.

    1978-01-01

    Suppression caused by five of the seven matrix elements studied (Si, Al, Fe, Ca and Mg) was observed in the atomic-absorption determination of manganese in geological materials, when synthetic solutions and the recommended oxidizing air-acetylene flame were used. The magnitude of the suppression effects depends on (1) the kind and concentration of the interfering elements, (2) the type of acid medium, and (3) the concentration of manganese to be determined. All interferences noted are removed or alleviated by using a reducing nitrous oxide-acetylene flame. The atomic-absorption method using this flame can be applied to the determination of total and extractable manganese in a wide range of geological materials without interferences. Analyses of six U.S. Geological Survey rock standards for manganese gave results in agreement with the reported values. ?? 1978.

  6. Development of reference materials to detect 15 different human papillomavirus genotypes.

    PubMed

    Rhee, Jee Eun; Kang, Young Soon; Seo, Hyun Hee; Choi, Ju-yeon; Kee, Mee-Kyung; Kim, Tae-Jin; Hong, Sung Ran; Kim, Sung Soon

    2014-06-10

    Accurate human papillomavirus (HPV) typing is essential for evaluating and monitoring HPV vaccines in cervical cancer screening and in epidemiological surveys. In our country, different HPV DNA detection and genotyping methodologies have been established for diagnosing and monitoring HPV-related disease in clinical practice and for research. However, there is a lack of reference materials to standardize the methods for HPV detection and genotyping. In this study, we constructed candidate reference materials comprising 15 targets (13 types of high-risk HPV, two types of low-risk HPV). We evaluated whether the candidate reference materials could be used as the reference for HPV detection and genotyping using quantitative real-time polymerase chain reaction. Standard curves for the wide linear range (10(1)-10(6)copies/μL) produced high correlation regression coefficient R(2) of 0.99. The reaction efficiencies were 96.3% to 101.2% for the standard curves, indicating highly efficient reactions. Specific genotypes were detected in single or multiple mixed samples. Our results suggest that these reference materials may provide useful standards for standardizing quality assurance for different HPV-typing assays and for proficiency testing in diagnostic laboratories.

  7. 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

  8. 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.

  9. 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.

  10. Reference materials produced for a European metrological research project focussing on measurements of NORM.

    PubMed

    Larijani, C; Pearce, A K; Regan, P H; Russell, B C; Jerome, S M; Crespo, M T; de Felice, P; Lutter, G; Maringer, F; Mazánová, M

    2017-02-08

    Reliable measurement of Naturally Occurring Radioactive Materials is of significance in order to comply with environmental regulations and for radiological protection purposes. This paper discusses the standardisation of three reference materials, namely sand, tuff and TiO2 to serve as quality control materials for traceability, method validation and instrument calibration. The sample preparation, material characterization via γ, α and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and the assignment of values for both the 4n (Thorium) and 4n+2 (Uranium) decay series are described.

  11. 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.

  12. Recent issues on development of reference materials and standardized tests of optical methods of strain measurement

    NASA Astrophysics Data System (ADS)

    Burguete, Richard; Hack, Erwin; Kujawinska, Malgorzata; Patterson, Eann; Salbut, Leszek; Saleem, Quasim; Siebert, Thorsten; Whelan, Maurice

    2005-06-01

    The need for standards in optical methods of strain measurement has been discussed previously and attention has switched to the creation of reference materials and standardised tests. Reference materials provide a means of calibrating a measurement system by comparison to a standard that is traceable to an international standard. In this way an unbroken chain of comparisons between the measurement system and the international standard with defined uncertainties in each comparison is created. A standardised test allows the performance of the measurement system to be assessed against a number of known quantities and such tests should be as challenging as the applications for which the measurement system has been designed. The preliminary design of a reference material for optical techniques of strain measurement are presented. Results obtained from the tests of these physical reference materials using digital image correlation, ESPI, grating (moire) interferometry, photoelasticity, strain gauges and thermoelasticity support the design hypothesis and have aided the refinement of the design. The first set of results produced with the new design showed remarkable correlation despite being obtained independently in four different laboratories in four different countries using six different techniques. Initial designs for a set of standard tests have also been created and some preliminary results will be presented. The concept of virtual standardised test materials has been introduced to allow the performance of the algorithms within a measurement system to be assessed so that a standard and comprehensive diagnostic and evaluation framework will be available to system designers, manufacturers and end-users.

  13. 10 CFR 51.109 - Public hearings in proceedings for issuance of materials license with respect to a geologic...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Title I of the Nuclear Waste Policy Act of 1982, as amended, unless: (1)(i) The action proposed to be... license with respect to a geologic repository. 51.109 Section 51.109 Energy NUCLEAR REGULATORY COMMISSION... National Environmental Policy Act-Regulations Implementing Section 102(2) Materials Licenses §...

  14. 10 CFR 51.109 - Public hearings in proceedings for issuance of materials license with respect to a geologic...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Title I of the Nuclear Waste Policy Act of 1982, as amended, unless: (1)(i) The action proposed to be... license with respect to a geologic repository. 51.109 Section 51.109 Energy NUCLEAR REGULATORY COMMISSION... National Environmental Policy Act-Regulations Implementing Section 102(2) Materials Licenses §...

  15. 10 CFR 51.109 - Public hearings in proceedings for issuance of materials license with respect to a geologic...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Title I of the Nuclear Waste Policy Act of 1982, as amended, unless: (1)(i) The action proposed to be... license with respect to a geologic repository. 51.109 Section 51.109 Energy NUCLEAR REGULATORY COMMISSION... National Environmental Policy Act-Regulations Implementing Section 102(2) Materials Licenses §...

  16. 10 CFR 51.109 - Public hearings in proceedings for issuance of materials license with respect to a geologic...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Title I of the Nuclear Waste Policy Act of 1982, as amended, unless: (1)(i) The action proposed to be... license with respect to a geologic repository. 51.109 Section 51.109 Energy NUCLEAR REGULATORY COMMISSION... National Environmental Policy Act-Regulations Implementing Section 102(2) Materials Licenses §...

  17. 10 CFR 51.109 - Public hearings in proceedings for issuance of materials license with respect to a geologic...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Title I of the Nuclear Waste Policy Act of 1982, as amended, unless: (1)(i) The action proposed to be... license with respect to a geologic repository. 51.109 Section 51.109 Energy NUCLEAR REGULATORY COMMISSION... National Environmental Policy Act-Regulations Implementing Section 102(2) Materials Licenses §...

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

    PubMed

    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.

  19. Freeze-drying for the stabilisation of shellfish toxins in mussel tissue (Mytilus edulis) reference materials.

    PubMed

    McCarron, Pearse; Emteborg, Håkan; Hess, Philipp

    2007-04-01

    Two samples of mussels (Mytilus edulis) were collected from the southwest of Ireland. One sample contained domoic acid, the other sample contained okadaic acid, dinophysistoxin-2 and azaspiracid-1, -2 and -3. Wet and freeze-dried reference materials were prepared from each of the two samples to test for differences in homogeneity, stability and extractability of the analytes in either condition. Wet materials were homogenised, aliquoted and hermetically sealed under argon and subsequently frozen at -80 degrees C. Dry materials were similarly homogenised but frozen in flat cakes prior to freeze-drying. After grinding, sieving and further homogenisation, the resulting powder was aliquoted and hermetically sealed. Domoic acid materials were characterised using HPLC-UV, while LC-MS was used for the determination of lipophilic toxins. The extractabilities of all phycotoxins studied were comparable for wet and freeze-dried materials once a sonication step had been carried out for reconstitution of the freeze-dried materials prior to extraction. Homogeneity was assessed through replicate analysis of the phycotoxins (n = 10), and was found to be similar for wet and freeze-dried materials, for both hydrophilic and lipophilic toxins. Water contents were determined for both wet and freeze-dried materials, and particle size was determined for the freeze-dried materials. Stability was evaluated isochronously over eight months at four temperatures (-20, +4, +20 and +40 degrees C). The freeze-dried material containing domoic acid was stable over the whole duration at all temperatures, while in the wet material domoic acid degraded to some extent at all temperatures except -20 degrees C. In freeze-dried and wet materials containing lipophilic toxins, okadaic acid, dinophysistoxin-2, azaspiracid-1 and azaspiracid-2 were stable over the whole duration at all conditions, while concentrations of azaspiracid-3 changed significantly in both materials at some storage temperatures. Figure

  20. 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.

  1. Polychloroprene flexible foam as a reference material. [for fire toxicity tests

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

    Polychloroprene flexible foam was evaluated as a reference material for fire toxicity tests. A commercial sample was evaluated using nine different test conditions of the USF methodology. The material exhibited a wide range of relative toxicity depending on the test conditions. Times to incapacitation and times to death were shortest at 16 ml/sec (1 l/min) air flow, at any fixed heating rate and upper limit temperature.

  2. Preparation of spiked grass for use as an environmental radioactivity reference material.

    PubMed

    Lourenço, V; Ferreux, L; Lacour, D; Le Garrérès, I; Morelli, S

    2014-05-01

    Measurement of radionuclides from environmental samples includes a wide variety of matrix compositions and densities. To improve the traceability of environmental monitoring, LNE-LNHB intends to produce mixed γ-ray reference materials with a known mass activity and a composition as representative as possible of real environmental samples. This paper describes the preparation and characterization of a low density treated grass matrix spiked with mixed γ-emitters. This material was used in a proficiency test exercise whose results are presented.

  3. 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).

  4. 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.

  5. 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).

  6. Specific Heat Capacity Measurement of Single-Crystalline Silicon as New Reference Material

    NASA Astrophysics Data System (ADS)

    Abe, Haruka; Kato, Hideyuki; Baba, Tetsuya

    2011-11-01

    We started to develop a new certified reference material for specific heat capacity measurement using a new type of cryogenic adiabatic calorimeter, applying a pulse-tube cryocooler in the temperature range from 50 to 350 K. A candidate certified reference material is single-crystalline silicon. To check the performance of the equipment, we measured the specific heat capacity of NIST SRM720, a type of synthetic sapphire. The relative expanded uncertainty of the measurement was estimated to be 0.65% at 350 K and 8.2% at 50 K, and the certified value of SRM720 was within the limits of uncertainty. In the next step, we measured the temperature dependence of the specific heat capacity of single-crystalline silicon. The result was compared with some reference data, and good agreement within 0.6% residual was found.

  7. 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.

  8. 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.…

  9. Field-Tested Reference Materials: A Survey of What Has Worked Best.

    ERIC Educational Resources Information Center

    McDonald, Brenda; And Others

    1993-01-01

    Presents an annotated bibliography of 33 reference items--including several CD-ROM products--published during 1991-92 that were recommended by librarians. Materials are listed in the following areas: general works; business, science, and technology; fine arts; history and genealogy; medicine and health; and social sciences and humanities. A…

  10. 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…

  11. 40 CFR 1048.810 - What materials does this part reference?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAE J2260, Nonmetallic Fuel System Tubing with One or More Layers, November 2004 1048.105 (b) ISO..., Switzerland or http://www.iso.org. Table 2 follows: Table 2 of § 1048.810—ISO Materials Document number and name Part 1048reference ISO 9141-2 Road vehicles—Diagnostic systems—Part 2: CARB requirements...

  12. 40 CFR 1048.810 - What materials does this part reference?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SAE J2260, Nonmetallic Fuel System Tubing with One or More Layers, November 2004 1048.105 (b) ISO..., Switzerland or http://www.iso.org. Table 2 follows: Table 2 of § 1048.810—ISO Materials Document number and name Part 1048reference ISO 9141-2 Road vehicles—Diagnostic systems—Part 2: CARB requirements...

  13. 41 CFR 102-117.170 - What reference materials are available to ship freight?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TRANSPORTATION 117-TRANSPORTATION MANAGEMENT Shipping Freight § 102-117.170 What reference materials are...: (1) U.S. Government Freight Transportation Handbook; (2) Limited Authority to Use Commercial Forms... are available to ship freight? 102-117.170 Section 102-117.170 Public Contracts and...

  14. 41 CFR 102-117.170 - What reference materials are available to ship freight?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... TRANSPORTATION 117-TRANSPORTATION MANAGEMENT Shipping Freight § 102-117.170 What reference materials are...: (1) U.S. Government Freight Transportation Handbook; (2) Limited Authority to Use Commercial Forms... are available to ship freight? 102-117.170 Section 102-117.170 Public Contracts and...

  15. 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 ...

  16. 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

  17. Optimal mapping of terrestrial gamma dose rates using geological parent material and aerogeophysical survey data.

    PubMed

    Rawlins, B G; Scheib, C; Tyler, A N; Beamish, D

    2012-12-01

    Regulatory authorities need ways to estimate natural terrestrial gamma radiation dose rates (nGy h⁻¹) across the landscape accurately, to assess its potential deleterious health effects. The primary method for estimating outdoor dose rate is to use an in situ detector supported 1 m above the ground, but such measurements are costly and cannot capture the landscape-scale variation in dose rates which are associated with changes in soil and parent material mineralogy. We investigate the potential for improving estimates of terrestrial gamma dose rates across Northern Ireland (13,542 km²) using measurements from 168 sites and two sources of ancillary data: (i) a map based on a simplified classification of soil parent material, and (ii) dose estimates from a national-scale, airborne radiometric survey. We used the linear mixed modelling framework in which the two ancillary variables were included in separate models as fixed effects, plus a correlation structure which captures the spatially correlated variance component. We used a cross-validation procedure to determine the magnitude of the prediction errors for the different models. We removed a random subset of 10 terrestrial measurements and formed the model from the remainder (n = 158), and then used the model to predict values at the other 10 sites. We repeated this procedure 50 times. The measurements of terrestrial dose vary between 1 and 103 (nGy h⁻¹). The median absolute model prediction errors (nGy h⁻¹) for the three models declined in the following order: no ancillary data (10.8) > simple geological classification (8.3) > airborne radiometric dose (5.4) as a single fixed effect. Estimates of airborne radiometric gamma dose rate can significantly improve the spatial prediction of terrestrial dose rate.

  18. Characterization of the Defense Waste Processing Facility (DWPF) Environmental Assessment (EA) glass Standard Reference Material. Revision 1

    SciTech Connect

    Jantzen, C.M.; Bibler, N.E.; Beam, D.C.; Crawford, C.L.; Pickett, M.A.

    1993-06-01

    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 Product Specifications (WAPS). The current Waste Acceptance Primary 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 (PCI). In order to be acceptable, a waste glass must be more durable during PCT analysis than the waste glass identified in the DWPF Environmental 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 and/or redox Standard Reference Material (SRM) for all waste form producers.

  19. A natural matrix (pureed tomato) candidate reference material containing residue concentrations of pesticide chemicals.

    PubMed

    Armishaw, P; Millar, R

    2001-06-01

    NARL (the Australian National Analytical Reference Laboratory) is preparing a pureed tomato reference material spiked with residue concentrations of a range of pesticide chemicals relevant to the Australian horticultural industry. Traceable certified pesticide concentration values will be established using both isotope dilution mass spectrometry primary methods (developed within NARL) and measurements carried out by a number of experienced laboratories. As far as we are aware, there is no other similar CRM available anywhere in the world. The need for such a material is evident from the results of interlaboratory proficiency studies conducted by NARL among Australian and Asia-Pacific residue testing laboratories. Many participants are experiencing difficulties with the analysis of pesticide residues in fruit and vegetables at concentrations of regulatory significance. Chemicals such as methamidophos (an organophosphorus pesticide widely used on tomato crops) are causing particular problems. In a pilot study, a number of units of control (unspiked tomato) and the candidate reference material were prepared and packaged into lacquered steel cans which were sealed and sterilised by immersion in boiling water. Accelerated stability testing of the packaged material was conducted using isochronous measurement. All of the pesticides showed some degree of degradation after 4 weeks of storage at 50 degrees C, and after 168 days of storage at room temperature. However, all appeared to be stable after 168 days of freezer storage. Homogeneity testing involved duplicate test portions taken from every 50th unit of reference material. An experimental protocol was devised with the aim of minimising the analytical variability and assuring the quality of the data generated. There is some degree of inhomogeneity in the prepared material and a small fill trend is also indicated. Potential improvements to the spiking and preparation procedure have been identified and it is planned to

  20. An Annotated Bibliography of Reference Materials for Use in a Junior-Senior High School Library Media Center.

    ERIC Educational Resources Information Center

    Whitely, Faye McConnell

    Designed to assist the librarian and/or teacher by serving as a checklist for a basic collection of reference materials, this annotated bibliography presents a list of reference sources that are appropriate for Alabama students in grades 7 through 12. The reference materials are intended to support the curriculum of a comprehensive public…

  1. Impact Craters on Earth: Lessons for Understanding Martian Geological Materials and Processes

    NASA Astrophysics Data System (ADS)

    Osinski, G. R.

    2015-12-01

    Impact cratering is one of the most ubiquitous geological processes in the Solar System and has had a significant influence on the geological evolution of Mars. Unlike the Moon and Mercury, the Martian impact cratering record is notably diverse, which is interpreted to reflect interactions during the impact process with target volatiles and/or the atmosphere. The Earth also possesses a volatile-rich crust and an atmosphere and so is one of the best analogues for understanding the effects of impact cratering on Mars. Furthermore, fieldwork at terrestrial craters and analysis of samples is critical to ground-truth observations made based on remote sensing data from Martian orbiters, landers, and rovers. In recent years, the effect of target lithology on various aspects of the impact cratering process has emerged as a major research topic. On Mars, volatiles have been invoked to be the primary factor influencing the morphology of ejecta deposits - e.g., the formation of single-, double- and multiple-layered ejecta deposits - and central uplifts - e.g., the formation of so-called "central pit" craters. Studies of craters on Earth have also shown that volatiles complicate the identification of impactites - i.e., rocks produced and/or affected by impact cratering. Identifying impactites on Earth is challenging, often requiring intensive and multi-technique laboratory analysis of hand specimens. As such, it is even more challenging to recognize such materials in remote datasets. Here, observations from the Haughton (d = 23 km; Canada), Ries (d = 24 km; Germany), Mistastin (d = 28 km; Canada), Tunnunik, (d = 28 km; Canada), and West Clearwater Lake (d = 36 km; Canada) impact structures are presented. First, it is shown that some impactites mimic intrusive, volcanic, volcanoclastic and in some cases sedimentary clastic rocks. Care should, therefore, be taken in the identification of seemingly unusual igneous rocks at rover landing sites as they may represent impact melt

  2. Some topics in English newsmagazines in autumn to winter, 2010, with special reference to the mining redevelopment of Afghanistan, review of rare earth elements mineral resources and current geological mapping

    NASA Astrophysics Data System (ADS)

    Takahashi, Yuhei

    Some topics in English newsmagazines in autumn to winter, 2010, with special reference to the mining redevelopment of Afghanistan, review of rare earth elements mineral resources and current geological mapping

  3. Image analysis techniques with special reference to analysis and interpretation of geological features from LANDSAT imagery. [India

    NASA Technical Reports Server (NTRS)

    Kamat, D. S.; Majumder, K. L.; Naik, S. D.; Swaminathan, V. L.

    1977-01-01

    The principal component analysis enhances the contrast existing between the different cover types present in an imagery. A procedure is presented with regards to the determination of the principal components. The method is tested for a portion of the LANDSAT imagery pertaining to Anantapur region. Another technique, using the concept of non-linear contrast stretching is defined and developed and carried out on the same imagery. The results are presented as photographs. An interpretation of the geology of the region is derived from these photographs.

  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.; ...

    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. A mussel tissue certified reference material for multiple phycotoxins. Part 1: design and preparation.

    PubMed

    McCarron, Pearse; Emteborg, Håkan; Nulty, Cíara; Rundberget, Thomas; Loader, Jared I; Teipel, Katharina; Miles, Christopher O; Quilliam, Michael A; Hess, Philipp

    2011-05-01

    The development of multi-analyte methods for lipophilic shellfish toxins based on liquid chromatography-mass spectrometry permits rapid screening and analysis of samples for a wide variety of toxins in a single run. Validated methods and appropriate certified reference materials (CRMs) are required to ensure accuracy of results. CRMs are essential for accurate instrument calibration, for assessing the complete analytical method from sample extraction to data analysis and for verifying trueness. However, CRMs have hitherto only been available for single toxin groups. Production of a CRM containing six major toxin groups was achieved through an international collaboration. Preparation of this material, CRM-FDMT1, drew on information from earlier studies as well as improved methods for isolation of toxins, handling bulk tissues and production of reference materials. Previous investigations of stabilisation techniques indicated freeze-drying to be a suitable procedure for preparation of shellfish toxin reference materials and applicable to a wide range of toxins. CRM-FDMT1 was initially prepared as a bulk wet tissue homogenate containing domoic acid, okadaic acid, dinophysistoxins, azaspiracids, pectenotoxin-2, yessotoxin and 13-desmethylspirolide C. The homogenate was then freeze-dried, milled and bottled in aliquots suitable for distribution and analysis. The moisture content and particle size distribution were measured, and determined to be appropriate. A preliminary toxin analysis of the final material showed a comprehensive toxin profile.

  6. Constraints on transportation of reagents, reference materials and samples, difficulties and possible solutions: a user's perspective.

    PubMed

    Blanchard, P C

    2006-01-01

    The air transportation of infectious materials is regulated by international air transport associations and based on United Nations Model regulations which have become more practical in addressing animal disease agents. However, individual countries' import and interstate requirements determine what materials can be imported and transported, and this approval process can be long, resulting in delays in organism confirmation, use of international OIE and other reference laboratories, and acquisition of reference materials, proficiency test panels, and reagents for performing necessary testing. Delays can be prevented for permits that are required for the routine work performed by a laboratory through the use of comprehensive and annually renewed permits. This process, however, does not address new and exotic agents where time is critical to an effective emergency response. This paper suggests actions by both the OIE and regulatory authorities which can assist in streamlining and expediting the permit process.

  7. Development of a Certified Reference Material for myeloperoxidase-anti-neutrophil cytoplasmic autoantibodies (MPO-ANCA).

    PubMed

    Monogioudi, Evanthia; Hutu, Dana Petronela; Martos, Gustavo; Sheldon, Joanna; Schimmel, Heinz; Meroni, Pier Luigi; Zegers, Ingrid

    2016-06-01

    A serum Certified Reference Material (CRM) for supporting reliable autoimmune diagnostics was recently released by the Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre of the European Commission. It was produced in collaboration with a Working Group on the Harmonisation of Autoimmune Tests of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC WG-HAT). This material is aimed at facilitating the standardisation of measurements of anti-myeloperoxidase immunoglobulin G antibodies. The CRM could be used as a common calibrant by clinicians and manufacturers thereby significantly improving the comparability of results from commercial immunoassays used for IgG anti-MPO measurements. This paper provides information on the new CRM and its intended use.

  8. Characterization and uncertainty evaluation of a new certified reference material of baicalein.

    PubMed

    Gong, Ningbo; Wang, Xiaoying; Zhang, Baoxi; Gao, Zhaolin; Du, Guanhua; Lv, Yang

    2014-02-01

    A new certified reference material (CRM) of baicalein was developed aiming to control the quality of baicalein and relative pharmaceuticals. Sample preparation, homogeneity, stability, value assignment, and uncertainty of a new certified reference material (CRM) of baicalein were presented in this paper. Characterization of the material relied on three different methods, which were differential scanning calorimetry (DSC), coulometric titration method (CT) and mass balance method. DSC and CT were used for purity determination of baicalein firstly. The certified value of baicalein CRM is 99.72% with an expanded uncertainty of 0.25% (k=2). The new CRM of baicalein can be used to validate analytical methods, improve the accuracy of measurement data as well as establish meteorological traceability of analytical results.

  9. 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.

  10. Material Units, Structures/Landforms, and Stratigraphy for the Global Geologic Map of Ganymede (1:15M)

    NASA Technical Reports Server (NTRS)

    Patterson, G. Wesley; Head, James W.; Collins, Geoffrey C.; Pappalardo, Robert T.; Prockter, Louis M.; Lucchitta, Baerbel K.

    2008-01-01

    In the coming year a global geological map of Ganymede will be completed that represents the most recent understanding of the satellite on the basis of Galileo mission results. This contribution builds on important previous accomplishments in the study of Ganymede utilizing Voyager data and incorporates the many new discoveries that were brought about by examination of Galileo data. Material units have been defined, structural landforms have been identified, and an approximate stratigraphy has been determined utilizing a global mosaic of the surface with a nominal resolution of 1 km/pixel assembled by the USGS. This mosaic incorporates the best available Voyager and Galileo regional coverage and high resolution imagery (100-200 m/pixel) of characteristic features and terrain types obtained by the Galileo spacecraft. This map has given us a more complete understanding of: 1) the major geological processes operating on Ganymede, 2) the characteristics of the geological units making up its surface, 3) the stratigraphic relationships of geological units and structures, and 4) the geological history inferred from these relationships. A summary of these efforts is provided here.

  11. Development of NIST standard reference material 2373: Genomic DNA standards for HER2 measurements.

    PubMed

    He, Hua-Jun; Almeida, Jamie L; Lund, Steve P; Steffen, Carolyn R; Choquette, Steve; Cole, Kenneth D

    2016-06-01

    NIST standard reference material (SRM) 2373 was developed to improve the measurements of the HER2 gene amplification in DNA samples. SRM 2373 consists of genomic DNA extracted from five breast cancer cell lines with different amounts of amplification of the HER2 gene. The five components are derived from the human cell lines SK-BR-3, MDA-MB-231, MDA-MB-361, MDA-MB-453, and BT-474. The certified values are the ratios of the HER2 gene copy numbers to the copy numbers of selected reference genes DCK, EIF5B, RPS27A, and PMM1. The ratios were measured using quantitative polymerase chain reaction and digital PCR, methods that gave similar ratios. The five components of SRM 2373 have certified HER2 amplification ratios that range from 1.3 to 17.7. The stability and homogeneity of the reference materials were shown by repeated measurements over a period of several years. SRM 2373 is a well characterized genomic DNA reference material that can be used to improve the confidence of the measurements of HER2 gene copy number.

  12. 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

  13. 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.

  14. Preparation and evaluation of candidate certified reference materials (CRMs) for nutrients in seawater.

    PubMed

    Smith, Kerry M; Wells, David E

    2007-07-01

    Certified reference materials (CRMs) are an essential part of the quality assurance (QA) necessary for the reliable analytical measurement of nutrients in seawater. The CRMs currently available for these analyses are not matrix matched to marine samples. QUASIMEME routinely produces test materials for the nutrients in seawater and nutrients in estuarine water and low-salinity open water Laboratory Performance Studies (LPS) that are both homogeneous and stable. QUASIMEME, in conjunction with Eurofins Scientific, Denmark have produced two reference materials (RMs). The homogeneity testing and preliminary stability studies were carried out by QUASIMEME, and the results are presented in this article. Participants of the QUASIMEME LPS who demonstrated satisfactory long-term performance for the analysis of nutrients in seawater and nutrients in estuarine water and low-salinity open water were invited to take part in the certification exercise. Twenty laboratories returned data, a summary of which is also presented. The certification and long-term stability testing and additional data analysis were carried out by Eurofins Scientific, Denmark, and are outwith the scope of this article and not reported here. Eurofins Scientific, Denmark have marketed these RMs as part of their range of VKI Reference Materials (further information is available from eurofins@eurofins.dk).

  15. Complete zircon and chromite digestion by sintering of granite, rhyolite, andesite and harzburgite rock reference materials for geochronological purposes

    NASA Astrophysics Data System (ADS)

    Bokhari, Syed Nadeem H.; Meisel, Thomas

    2014-05-01

    to be increased for an accurate content determination and complete release of analytes for geochronological studies. Larger test portion size reduces the heterogeneity issues in granites in particular [2]. No significant blanks issues were observed and interferences were controlled using QQQ MS mode of ICP-MS. References [1] Meisel, T., N. Schöner, et al. (2002). "Determination of Rare Earth Elements, Y, Th, Zr, Hf, Nb and Ta in Geological Reference Materials G-2, G-3, SCo-1 and WGB-1 by Sodium Peroxide Sintering and Inductively Coupled Plasma-Mass Spectrometry." Geostandards Newsletter 26(1): 53-61. [2] Bokhari SNH., Meisel T (2013) "The Determination of Homogeneity of Geological Reference Material" Mineralogical Magazine, 77(5): 731.

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

    PubMed

    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.

  17. Characterization of brown rice as a certified reference material for Fukushima accident-related radioactivity measurements.

    PubMed

    Unno, Yasuhiro; Hachinohe, Mayumi; Hamamatsu, Shioka; Todoriki, Setsuko; Yunoki, Akira; Miura, Tsutomu

    2014-05-01

    We developed a certified reference material of brown rice to measure radioactivity from the Fukushima Daiichi Nuclear Power Plant accident. The rice was planted in the spring of 2011, just after the Fukushima accident occurred, and it was harvested in the autumn of 2011. The certified value of radioactivity concentration in the rice was 33.6 Bq kg(-1) of Cs-134 and 51.8 Bq kg(-1) of Cs-137 on August 1, 2012. The reference material is being widely distributed by the National Metrology Institute of Japan. To determine the radioactivity and its uncertainties in the brown rice, we employed gamma-ray spectrometry with a high-purity germanium detector and Monte Carlo simulation.

  18. Standard reference materials (SRMs) for determination of organic contaminants in environmental samples.

    PubMed

    Wise, Stephen A; Poster, Dianne L; Kucklick, John R; Keller, Jennifer M; Vanderpol, Stacy S; Sander, Lane C; Schantz, Michele M

    2006-10-01

    For the past 25 years the National Institute of Standards and Technology (NIST) has developed certified reference materials (CRMs), known as standard reference materials (SRMs), for determination of organic contaminants in environmental matrices. Assignment of certified concentrations has usually been based on combining results from two or more independent analytical methods. The first-generation environmental-matrix SRMs were issued with certified concentrations for a limited number (5 to 10) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Improvements in the analytical certification approach significantly expanded the number and classes of contaminants determined. Environmental-matrix SRMs currently available include air and diesel particulate matter, coal tar, marine and river sediment, mussel tissue, fish oil and tissue, and human serum, with concentrations typically assigned for 50 to 90 organic contaminants, for example PAHs, nitro-substituted PAHs, PCBs, chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs).

  19. The production and certification of a plutonium equal-atom reference material: NBL CRM 128

    SciTech Connect

    Crawford, D.W. . Office of Safeguards and Security); Gradle, C.G.; Soriano, M.D. )

    1990-07-01

    This report describes the design, production, and certification of the New Brunswick Laboratory plutonium equal-atom certified reference material (CRM), NBL CRM 128. The primary use of this CRM is for the determination of bias corrections encountered in the operation of a mass spectrometer. This reference material is available to the US Department of Energy contractor-operated and government-operated laboratories, as well as to the international nuclear safeguards community. The absolute, or unbiased, certified value for the CRM's Pu-242/Pu-239 ratio is 1.00063 {plus minus} 0.00026 (95% confidence interval) as of October 1, 1984. This value was obtained through the quantitative blending of high-purity, chemically and isotopically characterized separated isotopes, as well as through intercomparisons of CRM samples with calibration mixtures using thermal ionization mass spectrometry. 32 tabs.

  20. Expanded polystyrene board as a standard reference material for thermal resistance measurement systems

    SciTech Connect

    Zarr, R.R.

    1997-11-01

    Thermal conductivity measurements at room temperature are presented as the basis for certified values of Standard Reference Material 1453, Expanded Polystyrene Board. The measurements have been conducted in accordance with a randomized full factorial experimental design of two variables, bulk density and temperature, using the National Institute of Standards and Technology one-meter line-heat-source guarded hot plate. Uncertainties of the measurements, consistent with current international guidelines, have been prepared. The thermal conductivity measurements were conducted over a range of bulk density of 37.4 to 45.8 kg/m{sup 3} and mean temperature of 281 to 313 K. Statistical analyses of the physical properties of Standard Reference Material 1453 are presented and include variations between boards, as well as within board.

  1. Laser ablation of advanced ceramics and glass-ceramic materials: Reference position dependence

    NASA Astrophysics Data System (ADS)

    Sola, D.; Escartín, A.; Cases, R.; Peña, J. I.

    2011-04-01

    In this work, we present the effect produced by modifying the reference position as well as the method of machining on the results obtained when advanced ceramics and glass-ceramic materials are machined by laser ablation. A Q-switched Nd:YAG laser at its fundamental wavelength of 1064 nm with pulsewidths in the nanosecond range has been used. Morphology, depth and volume obtained by means of pulse bursts and grooves have been studied. Working within the same laser conditions, it has been shown that these values depend on the thermal, optical and mechanical features of the material processed. We have also studied the variation in the ablation yield when the position of the surface to be machined is modified. Material properties and work conditions are related to the results obtained. We have described and discussed the morphology, composition, microstructure and hardness of the materials processed.

  2. 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.

  3. Determination of trace metals in marine biological reference materials by inductively coupled plasma mass spectrometry

    SciTech Connect

    Beauchemin, D.; McLaren, J.W.; Willie, S.N.; Berman, S.S.

    1988-04-01

    Inductively coupled plasma mass spectrometry (ICP-MS) was used for the analysis of two marine biological reference materials (dogfish liver tissue (DOLT-1) and dogfish muscle tissue (DORM-1)). The materials were put into solution by digestion in a nitric acid/hydrogen peroxide mixture. Thirteen elements (Na, Mg, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, Hg, and Pb) were then determined. Accurate results were obtained by standard additions or isotope dilution techniques for all of these elements in DORM-1 and for all but Cr in DOLT-1.

  4. Long-term stability of cellulose acetate butyrate thin films for nuclear certified reference materials.

    PubMed

    Buják, Renáta; Delva, Laurens; Erkoç, Mustafa; Bauwens, Jeroen; Jakopič, Rožle; Vincze, Laszlo; Aregbe, Yetunde; Cardon, Ludwig

    2017-01-01

    Characterization of cellulose acetate butyrate (CAB) thin films with 17, 35 and 52 wt% butyryl is carried out to select the most suitable matrix material for the U and Pu containing large-sized dried spike reference material. The virgin CAB samples were aged by vibrations, heat, humidity, UV light and X-rays. Characterization was done by thermo-analytical techniques, gel permeation chromatography, mechanical tests and via Rayleigh and Compton scattering. The results show that CAB with lower butyryl content can withstand higher operational temperatures and has greater mechanical strength while CAB with higher butyryl content seems to be more resistant to radiation.

  5. 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

  6. 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.

  7. 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

  8. Certified reference materials (GBW09170 and 09171) of creatinine in human serum.

    PubMed

    Dai, Xinhua; Fang, Xiang; Shao, Mingwu; Li, Ming; Huang, Zejian; Li, Hongmei; Jiang, You; Song, Dewei; He, Yajuan

    2011-02-15

    Creatinine is the most widely used clinical marker for assessing renal function. Concentrations of creatinine in human serum need to be carefully checked in order to ensure accurate diagnosis of renal function. Therefore, development of certified reference materials (CRMs) of creatinine in serum is of increasing importance. In this study, two new CRMs (Nos. GBW09170 and 09171) for creatinine in human serum have been developed. They were prepared with mixtures of several dozens of healthy people's and kidney disease patient's serum, respectively. The certified values of 8.10, 34.1 mg/kg for these two CRMs have been assigned by liquid chromatography-isotope dilution mass spectrometry (LC-IDMS) method which was validated by using standard reference material (SRM) of SRM909b (a reference material obtained from National Institute of Standards and Technology, NIST). The expanded uncertainties of certified values for low and high concentrations were estimated to be 1.2 and 1.1%, respectively. The certified values were further confirmed by an international intercomparison for the determination of creatinine in human serum (Consultative Committee for Amount of Substance, CCQM) of K80 (CCQM-K80). These new CRMs of creatinine in human serum pool are totally native without additional creatinine spiked for enrichment. These new CRMs are capable of validating routine clinical methods for ensuring accuracy, reliability and comparability of analytical results from different clinical laboratories. They can also be used for instrument validation, development of secondary reference materials, and evaluating the accuracy of high order clinical methods for the determination of creatinine in human serum.

  9. 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.

  10. Determination of Cd and Cr in an ABS candidate reference material by instrumental neutron activation analysis.

    PubMed

    Park, Kwangwon; Kang, Namgoo; Cho, Kyunghaeng; Lee, Jounghae

    2008-12-01

    In order to practically better cope with technical barriers to trade (TBT) of a great number of resin goods, our research presents first-ever results for the determination of Cd and Cr in acrylonitrile butadiene styrene (ABS) candidate reference material using instrumental neutron activation analysis (INAA) recently recognized as a candidate primary ratio method with a particular attention to the estimation of involved measurement uncertainties.

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

    DOE PAGES

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

    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

  12. Geology of the Williston basin, North Dakota, Montana, and South Dakota, with reference to subsurface disposal of radioactive wastes

    USGS Publications Warehouse

    Sandberg, C.A.

    1962-01-01

    The southern Williston basin, which underlies about 110,000 square miles #n North Dakota, South Dakota, and eastern Montana, is part of a large structural and sedimentary basin. Its surface is a flat to gently rolling plain, standing about 1,500 to 3,500 feet above sea level and locally studded by a few high buttes. The sedimentary sequence that fills the basin has a maximum thickness of about 16,700 feet and rests on Precambrian metamorphic rocks at depths of 500 to 13,900 feet below sea level. It contains rocks of every geologic system, from Cambrian to Quaternary. Rocks of Middle Cambrian through Middle Ordovician age are largely shale and sandstone, as much as 1,200 feet thick; rocks of Late Ordovician through Pennsylvanian age are largely limestone and dolomite, as much as 7,500 feet thick; and rocks of Permian through Tertiary age are predominantly shale and siltstone, as much as 8,000 feet thick. Pleistocene glacial drift mantles the northern and eastern parts of the area. Rocks of the Williston basin are gently folded and regional dips are 1? or less from the margins to the basin center. Dips on the flanks of the major anticlinal folds, the Nesson and cedar Creek anticlines and the Poplar and Bowdoin domes, generally are about 1? to 3? except on the steep west limb of the Cedar Creek anticline. The basin was shaped by Laramide orogeny during latest Cretaceous and early Tertiary time. Most of the present structural features, however, were initiated during the Precambrian and reactivated by several subsequent orogenies, of which the latest was the Laramide. The most important mineral resource of the area is oil, which is produced predominantly from the Paleozoic carbonate sequence and largely on three of the major anticlinal folds, and lignite, which is present near the surface in Paleocene rocks. The subsurface disposal of radioactive wastes at some places in the Williston basin appears to be geographically and geologically feasible. Many sites, at which

  13. 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.

  14. NIST gold nanoparticle reference materials do not induce oxidative DNA damage.

    PubMed

    Nelson, Bryant C; Petersen, Elijah J; Marquis, Bryce J; Atha, Donald H; Elliott, John T; Cleveland, Danielle; Watson, Stephanie S; Tseng, I-Hsiang; Dillon, Andrew; Theodore, Mellisa; Jackman, Joany

    2013-02-01

    One primary challenge in nanotoxicology studies is the lack of well-characterised nanoparticle reference materials which could be used as positive or negative nanoparticle controls. The National Institute of Standards and Technology (NIST) has developed three gold nanoparticle (AuNP) reference materials (10, 30 and 60 nm). The genotoxicity of these nanoparticles was tested using HepG2 cells and calf-thymus DNA. DNA damage was assessed based on the specific and sensitive measurement of four oxidatively-modified DNA lesions (8-hydroxy-2´-deoxyguanosine, 8-hydroxy-2´-deoxyadenosine, (5´S)-8,5´-cyclo-2´-deoxyadenosine and (5´R)-8,5´-cyclo-2´-deoxyadenosine) using liquid chromatography/tandem mass spectrometry. Significantly elevated, dose-dependent DNA damage was not detected at concentrations up to 0.2 μg/ml, and free radicals were not detected using electron paramagnetic resonance spectroscopy. These data suggest that the NIST AuNPs could potentially serve as suitable negative-control nanoparticle reference materials for in vitro and in vivo genotoxicity studies. NIST AuNPs thus hold substantial promise for improving the reproducibility and reliability of nanoparticle genotoxicity studies.

  15. Reference materials (RMs) for analysis of the human factor II (prothrombin) gene G20210A mutation.

    PubMed

    Klein, Christoph L; Márki-Zay, János; Corbisier, Philippe; Gancberg, David; Cooper, Susan; Gemmati, Donato; Halbmayer, Walter-Michael; Kitchen, Steve; Melegh, Béla; Neumaier, Michael; Oldenburg, Johannes; Leibundgut, Elisabeth Oppliger; Reitsma, Pieter H; Rieger, Sandra; Schimmel, Heinz G; Spannagl, Michael; Tordai, Attilia; Tosetto, Alberto; Visvikis, Sophie; Zadro, Renata; Mannhalter, Christine

    2005-01-01

    The Scientific Committee of Molecular Biology Techniques (C-MBT) in Clinical Chemistry of the IFCC has initiated a joint project in co-operation with the European Commission, Joint Research Centre, Institute of Reference Materials and Measurements to develop and produce plasmid-type reference materials (RMs) for the analysis of the human prothrombin gene G20210A mutation. Although DNA tests have a high impact on clinical decision-making and the number of tests performed in diagnostic laboratories is high, issues of quality and quality assurance exist, and currently only a few RMs for clinical genetic testing are available. A gene fragment chosen was produced that spans all primer annealing sites published to date. Both the wild-type and mutant alleles of this gene fragment were cloned into a pUC18 plasmid and two plasmid RMs were produced. In addition, a mixture of both plasmids was produced to mimic the heterozygous genotype. The present study describes the performance of these reference materials in a commutability study, in which they were tested by nine different methods in 13 expert laboratories. This series of plasmid RMs are, to the best of our knowledge, the first plasmid-type clinical genetic RMs introduced worldwide.

  16. 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.

  17. The Enigmatic Longevity of Granular Materials on Mars: The Case for Geologically Episodic Dune Formation

    NASA Technical Reports Server (NTRS)

    Marshall, J.

    1999-01-01

    Martian sand dunes are concentrated in vast sand seas in the circumpolar belt of the planet's northern hemisphere, but they are also pervasive over the whole planet. Their occurrence is to be expected on a super-arid planetary surface subjected to boundary layer drag from a continually active atmosphere. Whilst their occurrence is to be expected, their survival is enigmatic. But the enigma only arises if the martian system is considered similar to Earth's --where sand is moved highly frequently, more or less on a seasonal basis. Experimentally it is readily demonstrated that active sand will soon wear down to small grains and eventually diminish to below the critical sand size required to sustain dune formation. According to conventional wisdom, sand moves at higher speeds on Mars than on Earth, and if it were to move as frequently as it does on Earth, then the dune-forming sand population should have long since disappeared, given the great longevity of the martian aeolian system (Sagan coined the term "kamikaze" grains to express this disappearance). No supply of sand could keep pace with this depletion, especially in light of the fact that Mars does not have very active weathering, nor significant crustal differentiation. On Earth, plate tectonics, magmatic activity, and general crustal differentiation over geological time have produced great concentrations of quartz crystals in the continental crustal masses. Not only are these quartz grains chemically and mechanically resilient, they are about the right size for being transported by either wind or water. Add to this, the geologically recent contribution of glacial grinding, and it is easy to see why there are dune field on Earth. So what are the martian dunes composed of, and how does the material survive the eons of attrition? In addition to experimental demonstrations of sand comminution in laboratory aeolian simulations, the problem can be approached from first principles. Sagan showed that by simple

  18. Full-Vector, Low-Temperature Magnetic Measurements of Geologic Materials

    NASA Astrophysics Data System (ADS)

    Feinberg, J.; Sølheid, P.; Bowles, J. A.; Jackson, M. J.; Moskowitz, B. M.

    2010-12-01

    The magnetic properties of geologic materials offer insights into an enormous range of important geophysical phenomena ranging from core dynamics to paleoclimate. Low-temperature (<300 K) magnetic behavior can indicate the dominant magnetic mineral phases in a sample, determine the grain size distribution of the constituent magnetic minerals, and even reveal evidence of biogenic iron minerals. Low-temperature cycling across the magnetite Verwey transition is sometimes used to remove remanence associated with multi-domain grains, which is undesirable for paleointensity and other paleomagnetic experiments. Despite the utility of low-temperature magnetic data, probing these low-temperature phenomena from the perspective of understanding the underlying physical behavior has been hampered by instrumental limitations. Until now, nearly all measurements of low-temperature magnetization have been single-axis and are rarely done in true zero-field environments. Low-temperature remanence measurements at the Institute for Rock Magnetism (IRM) have been carried out almost exclusively on the Quantum Designs Magnetic Properties Measurement System (MPMS) where magnetization is measured only in the vertical direction, and “zero-fields” of up to 1 μT are common. The IRM - with funding from the Instrumentation and Facilities Program of the National Science Foundation, Earth Science Division, and in conjunction with ColdEdge Technologies (Allentown, Pennsylvania) - is developing a low-cost, cryogenic insert designed to work with a standard, horizontal-loading, 2G Enterprises magnetometer. Full three-axis measurements may now be made in ultra-low-field environments (nT) from ~17 K to room temperature. The design is compatible with both the large (7.6 cm) and small (4.2 cm) bore magnetometers, as well as many standard pulse magnetizers. Used in conjunction with the in-line degausser on the IRM’s pass-through magnetometer, it will ultimately be possible to acquire anhysteretic

  19. Consensus evaluation of radioactivity-in-soil reference materials in the context of an NPL Environmental Radioactivity Proficiency Test Exercise.

    PubMed

    Dean, Julian; Collins, Sean; Garcia Miranda, Maria; Ivanov, Peter; Larijani, Cyrus; Woods, Selina

    2017-01-25

    The development of two radioactivity-in-soil reference materials is described - one for peat and one for soil with high sand content. Each bulk material was processed, subdivided and measured before being sent to participants in an NPL Environmental Radioactivity Proficiency Test Exercise. Activity concentrations of radionuclides in each material were determined by 'consensus' evaluations of participants' results using two weighted mean methods. The project demonstrated the use of such exercises in delivering reference materials to the user community.

  20. 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.

  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.

  2. 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.

  3. Determination of polychlorinated biphenyl congeners and chlorinated pesticides in a fish tissue standard reference material.

    PubMed

    Poster, Dianne L; Kucklick, John R; Schantz, Michele M; Porter, Barbara J; Leigh, Stefan D; Wise, Stephen A

    2003-01-01

    The concentrations of a wide range of polychlorinated biphenyl congeners (PCBs) and chlorinated pesticides in a fish tissue Standard Reference Material (SRM) have been determined using multiple methods of analysis. This material, SRM 1946, Lake Superior Fish Tissue, was recently issued by the National Institute of Standards and Technology (NIST) and complements a suite of marine environmental natural-matrix SRMs that are currently available from NIST for the determination of organic contaminants such as aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), PCBs, and chlorinated pesticides. SRM 1946 is a fresh tissue homogenate (frozen) prepared from filleted adult lake trout (Salvelinus namaycush namaycush) collected from the Apostle Islands region of Lake Superior. SRM 1946 has certified and reference concentrations for PCB congeners, including the three non- ortho PCB congeners, and chlorinated pesticides. Certified concentrations are available for 30 PCB congeners and 15 chlorinated pesticides. Reference concentrations are available for 12 PCB congeners and 2 chlorinated pesticides. In addition, SRM 1946 is characterized for additional chemical constituents and properties: fatty acids, extractable fat, methylmercury, total mercury, selected trace elements, proximates, and caloric content. The characterization of chlorinated compounds is described in this paper with an emphasis on the approach used for the certification of the concentrations of PCB congeners and chlorinated pesticides. The PCB congener and chlorinated pesticide data are also compared to concentrations in other marine natural-matrix reference materials available from NIST (fish oil, mussel tissue, whale blubber, and a second fresh frozen fish tissue homogenate prepared from filleted adult lake trout collected from Lake Michigan) and from other organizations such as the National Research Council Canada (ground whole carp), the International Atomic Energy Agency (fish homogenate), and the

  4. 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

  5. Spark ablation-inductively coupled plasma spectrometry for analysis of geologic materials

    USGS Publications Warehouse

    Golightly, D.W.; Montaser, A.; Smith, B.L.; Dorrzapf, A.F.

    1989-01-01

    Spark ablation-inductively coupled plasma (SA-ICP) spectrometry is applied to the measurement of hafnium-zirconium ratios in zircons and to the determination of cerium, cobalt, iron, lead, nickel and phosphorus in ferromanganese nodules. Six operating parameters used for the high-voltage spark and argon-ICP combination are established by sequential simplex optimization of both signal-to-background ratio and signal-to-noise ratio. The time-dependences of the atomic emission signals of analytes and matrix elements ablated from a finely pulverized sample embedded in a pressed disk of copper demonstrate selective sampling by the spark. Concentration ratios of hafnium to zirconium in zircons are measured with a precision of 4% (relative standard deviation, RSD). For ferromanganese nodules, spectral measurements based on intensity ratios of analyte line to the Mn(II) 257.610 nm line provide precisions of analysis in the range from 7 to 14% RSD. The accuracy of analysis depends on use of standard additions of the reference material USGS Nod P-1, and an independent measurement of the Mn concentration. ?? 1989.

  6. 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.

  7. 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.

  8. An international evaluation of holmium oxide solution reference materials for wavelength calibration in molecular absorption spectrophotometry.

    PubMed

    Travis, John C; Zwinkels, Joanne C; Mercader, Flora; Ruíz, Arquímedes; Early, Edward A; Smith, Melody V; Noël, Mario; Maley, Marissa; Kramer, Gary W; Eckerle, Kenneth L; Duewer, David L

    2002-07-15

    Commercial spectrophotometers typically use absorption-based wavelength calibration reference materials to provide wavelength accuracy for their applications. Low-mass fractions of holmium oxide (Ho2O3) in dilute acidic aqueous solution and in glass matrixes have been favored for use as wavelength calibration materials on the basis of spectral coverage and absorption band shape. Both aqueous and glass Ho2O3 reference materials are available commercially and through various National Metrology Institutes (NMIs). Three NMIs of the North American Cooperation in Metrology (NORAMET) have evaluated the performance of Ho3-(aq)-based Certified Reference Materials (CRMs) under "routine" operating conditions using commercial instrumentation. The study was not intended to intercompare national wavelength scales but to demonstrate comparability of wavelength measurements among the participants and between two versions of the CRMs. It was also designed to acquire data from a variety of spectrophotometers for use in a NIST study of wavelength assignment algorithms and to provide a basis for a possible reassessment of NIST-certified Ho3+(aq) band locations. The resulting data show a substantial level of agreement among laboratories, instruments, CRM preparations, and peak-location algorithms. At the same time, it is demonstrated that the wavelength comparability of the five participating instruments can actually be improved by calibrating all of the instruments to the consensus Ho3+(aq) band locations. This finding supports the value of absorption-based wavelength standards for calibrating absorption spectrophotometers. Coupled with the demonstrated robustness of the band position values with respect to preparation and measurement conditions, it also supports the concept of extending the present approach to additional NMIs in order to certify properly prepared dilute acidic Ho2O3 solution as an intrinsic wavelength standard.

  9. Geochemical Analyses of Geologic Materials from Areas of Critical Environmental Concern, Clark and Nye Counties, Nevada

    USGS Publications Warehouse

    Ludington, Steve; Castor, Stephen B.; Budahn, James R.; Flynn, Kathryn S.

    2005-01-01

    INTRODUCTION An assessment of known and undiscovered mineral resources of selected areas administered by the Bureau of Land Management (BLM) in Clark and Nye Counties, Nevada was conducted by the U.S. Geological Survey (USGS), Nevada Bureau of Mines and Geology (NBMG), and University of Nevada, Las Vegas (UNLV). The purpose of this work was to provide the BLM with information for use in their long-term planning process in southern Nevada so that they can make better-informed decisions. The results of the assessment are in Ludington (2006). Existing information about the areas, including geology, geophysics, geochemistry, and mineral-deposit information was compiled, and field examinations of selected areas and mineral occurrences was conducted. This information was used to determine the geologic setting, metallogenic characteristics, and mineral potential of the areas. Twenty-five Areas of Critical Environmental Concern (ACECs) were identified by BLM as the object of this study. They range from tiny (less than one km2) to large (more than 1,000 km2). The location of the study areas is shown on Figure 1. This report includes geochemical data for rock samples collected by staff of the USGS and NBMG in these ACECs and nearby areas. Samples have been analyzed from the Big Dune, Ash Meadows, Arden, Desert Tortoise Conservation Center, Coyote Springs Valley, Mormon Mesa, Virgin Mountains, Gold Butte A and B, Whitney Pockets, Rainbow Gardens, River Mountains, and Piute-Eldorado Valley ACECs.

  10. Characterization of a Recombinant Adeno-Associated Virus Type 2 Reference Standard Material

    PubMed Central

    Lock, Martin; McGorray, Susan; Auricchio, Alberto; Ayuso, Eduard; Beecham, E. Jeffrey; Blouin-Tavel, Véronique; Bosch, Fatima; Bose, Mahuya; Byrne, Barry J.; Caton, Tina; Chiorini, John A.; Chtarto, Abdelwahed; Clark, K. Reed; Conlon, Thomas; Darmon, Christophe; Doria, Monica; Douar, Anne; Flotte, Terence R.; Francis, Joyce D.; Francois, Achille; Giacca, Mauro; Korn, Michael T.; Korytov, Irina; Leon, Xavier; Leuchs, Barbara; Lux, Gabriele; Melas, Catherine; Mizukami, Hiroaki; Moullier, Philippe; Müller, Marcus; Ozawa, Keiya; Philipsberg, Tina; Poulard, Karine; Raupp, Christina; Rivière, Christel; Roosendaal, Sigrid D.; Samulski, R. Jude; Soltys, Steven M.; Surosky, Richard; Tenenbaum, Liliane; Thomas, Darby L.; van Montfort, Bart; Veres, Gabor; Wright, J. Fraser; Xu, Yili; Zelenaia, Olga; Zentilin, Lorena

    2010-01-01

    Abstract A recombinant adeno-associated virus serotype 2 Reference Standard Material (rAAV2 RSM) has been produced and characterized with the purpose of providing a reference standard for particle titer, vector genome titer, and infectious titer for AAV2 gene transfer vectors. Production and purification of the reference material were carried out by helper virus–free transient transfection and chromatographic purification. The purified bulk material was vialed, confirmed negative for microbial contamination, and then distributed for characterization along with standard assay protocols and assay reagents to 16 laboratories worldwide. Using statistical transformation and modeling of the raw data, mean titers and confidence intervals were determined for capsid particles ({X}, 9.18 × 1011 particles/ml; 95% confidence interval [CI], 7.89 × 1011 to 1.05 × 1012 particles/ml), vector genomes ({X}, 3.28 × 1010 vector genomes/ml; 95% CI, 2.70 × 1010 to 4.75 × 1010 vector genomes/ml), transducing units ({X}, 5.09 × 108 transducing units/ml; 95% CI, 2.00 × 108 to 9.60 × 108 transducing units/ml), and infectious units ({X}, 4.37 × 109 TCID50 IU/ml; 95% CI, 2.06 × 109 to 9.26 × 109 TCID50 IU/ml). Further analysis confirmed the identity of the reference material as AAV2 and the purity relative to nonvector proteins as greater than 94%. One obvious trend in the quantitative data was the degree of variation between institutions for each assay despite the relatively tight correlation of assay results within an institution. This relatively poor degree of interlaboratory precision and accuracy was apparent even though attempts were made to standardize the assays by providing detailed protocols and common reagents. This is the first time that such variation between laboratories has been thoroughly documented and the findings emphasize the need in the field for universal reference standards. The rAAV2 RSM has been deposited

  11. 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 ...

  12. Thermocyclic stability of candidate Seebeck coefficient standard reference materials at high temperature

    NASA Astrophysics Data System (ADS)

    Martin, Joshua; Wong-Ng, Winnie; Caillat, Thierry; Yonenaga, I.; Green, Martin L.

    2014-05-01

    The Seebeck coefficient is the most widely measured property specific to thermoelectric materials. There is currently no consensus on measurement protocols, and researchers employ a variety of techniques to measure the Seebeck coefficient. The implementation of standardized measurement protocols and the use of reliable Seebeck Coefficient Standard Reference Materials (SRMs®) will allow the accurate interlaboratory comparison and validation of materials data, thereby accelerating the development and commercialization of more efficient thermoelectric materials and devices. To enable members of the thermoelectric materials community the means to calibrate Seebeck coefficient measurement equipment, NIST certified SRM® 3451 "Low Temperature Seebeck Coefficient Standard (10 K to 390 K)". Due to different practical requirements in instrumentation, sample contact methodology, and thermal stability, a complementary SRM® is required for the high temperature regime (300 K to 900 K). The principal requirement of a SRM® for the Seebeck coefficient at high temperature is thermocyclic stability. We therefore characterized the thermocyclic behavior of the Seebeck coefficient for a series of candidate materials: constantan, p-type single crystal SiGe, and p-type polycrystalline SiGe, by measuring the temperature dependence of the Seebeck coefficient as a function of 10 sequential thermal cycles, between 300 K and 900 K. We employed multiple regression analysis to interpolate and analyze the thermocyclic variability in the measurement curves.

  13. Geology of the Powder River Basin, Wyoming and Montana, with reference to subsurface disposal of radioactive wastes

    USGS Publications Warehouse

    Beikman, Helen M.

    1962-01-01

    The Powder River Basin is a structural and topographic basin occupying an area of about 20,000 square miles in northeastern Wyoming arid southeastern Montana. The Basin is about 230 miles long in a northwest-southeast direction and is about 100 miles wide. It is bounded on three sides by mountains in which rocks of Precambrian age are exposed. The Basin is asymmetrical with a steep west limb adjacent to the Bighorn Mountains and a gentle east limb adjacent to the Black Hills. Sedimentary rocks within the Basin have a maximum thickness of about 18,000 feet and rocks of every geologic period are represented. Paleozoic rocks are about 2,500 feet thick and consist of marine bonate rocks and sandstone; Mesozoic rocks are about 9,500 feet thick and consist of both marine and nonmarine siltstone and sandstone; and Cenozoic rocks are from 4,000 to 6,000 feet thick and consist of coal-bearing sandstone and shale. Radioactive waste could be stored in the pore space of permeable sandstone or in shale where space could be developed. Many such rock units that could be used for storing radioactive wastes are present within the Powder River Basin. Permeable sandstone beds that may be possible reservoirs for storage of radioactive waste are present throughout the Powder River Basin. These include sandstone beds in the Flathead Sandstone and equivalent strata in the Deadwood Formation, the Tensleep Sandstone and equivalent strata in the Minnelusa Formation and the Sundance Formation in rocks of pre-Cretaceous age. However, most of the possible sandstone reservoirs are in rocks of Cretaceous age and include sandstone beds in the Fall River, Lakota, Newcastle, Frontier, Cody, and Mesaverde Formations. Problems of containment of waste such as clogging of pore space and chemical incompatibility would have to be solved before a particular sandstone unit could be selected for waste disposal. Several thick sequences of impermeable shale such as those in the Skull Creek, Mowry, Frontier

  14. Geologic Time.

    ERIC Educational Resources Information Center

    Albritton, Claude C., Jr.

    1984-01-01

    Discusses the historical development of the concept of geologic time. Develops the topic by using the major discoveries of geologists, beginning with Steno and following through to the discovery and use of radiometric dating. An extensive reference list is provided. (JM)

  15. Determination of arsenic, antimony, bismuth, cadmium, copper, lead, molybdenum, silver and zinc in geological materials by atomic-absorption spectrometry

    USGS Publications Warehouse

    Viets, J.G.; O'Leary, R. M.; Clark, Robert J.

    1984-01-01

    Arsenic, antimony, bismuth, cadmium, copper, lead, molybdenum, silver and zinc are very useful elements in geochemical exploration. In the proposed method, geological samples are fused with potassium pyrosulphate and the fusate is dissolved in a solution of hydrochloric acid, ascorbic acid and potassium iodide. When this solution is shaken with a 10% V/V Aliquat 336 - isobutyl methyl ketone organic phase, the nine elements of interest are selectively partitioned in the organic phase. All nine elements can then be determined in the organic phase using flame atomic-absorption spectrometry. The method is rapid and allows the determination of Ag and Cd at levels down to 0.1 p.p.m., Cu, Mo, and Zn down to 0.5 p.p.m., Pb, Bi and Sb down to 1 p.p.m. and As down to 5 p.p.m. in geological materials.

  16. Proposed program for and present status of the Geological Survey's investigation of domestic resources of radioactive raw materials

    USGS Publications Warehouse

    Bulter, A.P.; Killeen, P.L.; Page, G.B.; Rubey, W.W.

    1983-01-01

    This interim report is designed to show the present status of the Geological Survey's information and the parts of a comprehensive program necessary to improve our information about the raw material resources of uranium and thorium. Rarely in geologic work has it been necessary. to determine so completely a nation's resources of useful minerals in so brief a span of time. Ordinarily, information on mineral resources Is accumulated during a long period of years. However, uranium and thorium were suddenly thrust from a position of subsidiary economic interest into one of great strategic importance. Information concerning their occurrence must, therefore, be obtained as rapidly as reliable methods of investigation will permit. Accordingly the program must be at once comprehensive and carried out over an area more extensive than is usual in the search for and appraisal of most other mineral resources.

  17. Development and certification of a standard reference material for vitamin D metabolites in human serum.

    PubMed

    Phinney, Karen W; Bedner, Mary; Tai, Susan S-C; Vamathevan, Veronica V; Sander, Lane C; Sharpless, Katherine E; Wise, Stephen A; Yen, James H; Schleicher, Rosemary L; Chaudhary-Webb, Madhulika; Pfeiffer, Christine M; Betz, Joseph M; Coates, Paul M; Picciano, Mary Frances

    2012-01-17

    The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health's Office of Dietary Supplements (NIH-ODS), has developed a Standard Reference Material (SRM) for the determination of 25-hydroxyvitamin D [25(OH)D] in serum. SRM 972 Vitamin D in Human Serum consists of four serum pools with different levels of vitamin D metabolites and has certified and reference values for 25(OH)D(2), 25(OH)D(3), and 3-epi-25(OH)D(3). Value assignment of this SRM was accomplished using a combination of three isotope-dilution mass spectrometry approaches, with measurements performed at NIST and at the Centers for Disease Control and Prevention (CDC). Chromatographic resolution of the 3-epimer of 25(OH)D(3) proved to be essential for accurate determination of the metabolites.

  18. Challenges in the size analysis of a silica nanoparticle mixture as candidate certified reference material

    NASA Astrophysics Data System (ADS)

    Kestens, Vikram; Roebben, Gert; Herrmann, Jan; Jämting, Åsa; Coleman, Victoria; Minelli, Caterina; Clifford, Charles; De Temmerman, Pieter-Jan; Mast, Jan; Junjie, Liu; Babick, Frank; Cölfen, Helmut; Emons, Hendrik

    2016-06-01

    A new certified reference material for quality control of nanoparticle size analysis methods has been developed and produced by the Institute for Reference Materials and Measurements of the European Commission's Joint Research Centre. The material, ERM-FD102, consists of an aqueous suspension of a mixture of silica nanoparticle populations of distinct particle size and origin. The characterisation relied on an interlaboratory comparison study in which 30 laboratories of demonstrated competence participated with a variety of techniques for particle size analysis. After scrutinising the received datasets, certified and indicative values for different method-defined equivalent diameters that are specific for dynamic light scattering (DLS), centrifugal liquid sedimentation (CLS), scanning and transmission electron microscopy (SEM and TEM), atomic force microscopy (AFM), particle tracking analysis (PTA) and asymmetrical-flow field-flow fractionation (AF4) were assigned. The value assignment was a particular challenge because metrological concepts were not always interpreted uniformly across all participating laboratories. This paper presents the main elements and results of the ERM-FD102 characterisation study and discusses in particular the key issues of measurand definition and the estimation of measurement uncertainty.

  19. Human urine certified reference material CZ 6009: creatinine, styrene metabolites (mandelic acid and phenylglyoxylic acid).

    PubMed

    Sperlingová, I; Dabrowská, L; Stránský, V; Kucera, J; Tichý, M

    2004-03-01

    The reference material was prepared by freeze-drying pooled urine samples obtained from healthy persons occupationally exposed to styrene. The concentrations of mandelic acid (MA), phenylglyoxylic acid (PGA), and hippuric acid (HA) in urine were determined by three modes of high-performance liquid chromatography (HPLC). For isochronous stability testing the urinary mandelic acid and phenylglyoxylic acid concentrations were followed over a 24-month period for a preliminary batch by use of HPLC. No changes of the concentration values were found. The creatinine concentration was stable for more than five years. Standard Reference Material NIST 914a Creatinine was used for traceability purposes for creatinine. Pure chemicals MA and PGA were used for traceability purposes. Control material ClinChek-Urine Control (Recipe) was analyzed simultaneously. The mean values of MA and PGA compare well with the means and fall within the control range of control samples. Results from homogeneity, stability, and traceability testing were evaluated using the statistical program ANOVA. The certified values and their uncertainties were evaluated from the results of interlaboratory comparisons, and homogeneity and stability tests. The values are unweighed arithmetical averages of accepted results and their uncertainties are combined uncertainties (coverage factor=1).

  20. Challenges in the size analysis of a silica nanoparticle mixture as candidate certified reference material.

    PubMed

    Kestens, Vikram; Roebben, Gert; Herrmann, Jan; Jämting, Åsa; Coleman, Victoria; Minelli, Caterina; Clifford, Charles; De Temmerman, Pieter-Jan; Mast, Jan; Junjie, Liu; Babick, Frank; Cölfen, Helmut; Emons, Hendrik

    A new certified reference material for quality control of nanoparticle size analysis methods has been developed and produced by the Institute for Reference Materials and Measurements of the European Commission's Joint Research Centre. The material, ERM-FD102, consists of an aqueous suspension of a mixture of silica nanoparticle populations of distinct particle size and origin. The characterisation relied on an interlaboratory comparison study in which 30 laboratories of demonstrated competence participated with a variety of techniques for particle size analysis. After scrutinising the received datasets, certified and indicative values for different method-defined equivalent diameters that are specific for dynamic light scattering (DLS), centrifugal liquid sedimentation (CLS), scanning and transmission electron microscopy (SEM and TEM), atomic force microscopy (AFM), particle tracking analysis (PTA) and asymmetrical-flow field-flow fractionation (AF4) were assigned. The value assignment was a particular challenge because metrological concepts were not always interpreted uniformly across all participating laboratories. This paper presents the main elements and results of the ERM-FD102 characterisation study and discusses in particular the key issues of measurand definition and the estimation of measurement uncertainty.

  1. 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.

  2. A comprehensive multiscale moisture transport analysis: From porous reference silicates to cement-based materials

    NASA Astrophysics Data System (ADS)

    Chemmi, H.; Petit, D.; Tariel, V.; Korb, J.-P.; Denoyel, R.; Bouchet, R.; Levitz, P.

    2015-07-01

    Natural and manufactured disordered systems are ubiquitous and often involve hierarchical structures. This structural organization optimizes defined physical properties at several scales from molecular to representative volumes where the usual homogenization approach becomes efficient. For studying a particular physical property on these systems it is thus required to use a general method of analysis based on the joint application of complementary techniques covering the whole set of time-and length-scales. Here we review a comprehensive multiscale method presented for analyzing the three-dimensional moisture transport in hierarchical porous media such as synthesized reference silicates and cement-based materials. Several techniques (NMR spectroscopy, relaxometry, diffusometry, X-ray micro-tomography, conductivity…) have been used to evidence the interplay between the different scales involved in this transport process. This method allows answering the general opened questions concerning the scale dependence of such a moisture transport in cement-based materials. We outline the main results of the multiscale techniques applied on reference porous silicates allowing separating the impact of geometry, hydric state and wettability on the moisture transport. Based on this approach, we prove that this transport at micro- and meso-scale is determinant to modify the moisture at macro-scale during setting or for hardened cement-based materials.

  3. Development of saw palmetto (Serenoa repens) fruit and extract standard reference materials.

    PubMed

    Schantz, Michele M; Bedner, Mary; Long, Stephen E; Molloy, John L; Murphy, Karen E; Porter, Barbara J; Putzbach, Karsten; Rimmer, Catherine A; Sander, Lane C; Sharpless, Katherine E; Thomas, Jeanice B; Wise, Stephen A; Wood, Laura J; Yen, James H; Yarita, Takashi; NguyenPho, Agnes; Sorenson, Wendy R; Betz, Joseph M

    2008-10-01

    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 two standard reference materials (SRMs) representing different forms of saw palmetto (Serenoa repens), SRM 3250 Serenoa repens fruit and SRM 3251 Serenoa repens extract. Both of these SRMs have been characterized for their fatty acid and phytosterol content. The fatty acid concentration values are based on results from gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS) analysis while the sterol concentration values are based on results from GC-FID and liquid chromatography with mass spectrometry analysis. In addition, SRM 3250 has been characterized for lead content, and SRM 3251 has been characterized for the content of beta-carotene and tocopherols. SRM 3250 (fruit) has certified concentration values for three phytosterols, 14 fatty acids as triglycerides, and lead along with reference concentration values for four fatty acids as triglycerides and 16 free fatty acids. SRM 3251 (extract) has certified concentration values for three phytosterols, 17 fatty acids as triglycerides, beta-carotene, and gamma-tocopherol along with reference concentration values for three fatty acids as triglycerides, 17 fatty acids as free fatty acids, beta-carotene isomers, and delta-tocopherol and information values for two phytosterols. These SRMs will complement other reference materials currently available with concentrations for similar analytes and are part of a series of SRMs being developed for dietary supplements.

  4. Nanomaterials for environmental studies: classification, reference material issues, and strategies for physico-chemical characterisation.

    PubMed

    Stone, Vicki; Nowack, Bernd; Baun, Anders; van den Brink, Nico; Kammer, Frank von der; Dusinska, Maria; Handy, Richard; Hankin, Steven; Hassellöv, Martin; Joner, Erik; Fernandes, Teresa F

    2010-03-01

    NanoImpactNet is a European Commission Framework Programme 7 (FP7) funded project that provides a forum for the discussion of current opinions on nanomaterials in relation to human and environmental issues. In September 2008, in Zurich, a NanoImpactNet environmental workshop focused on three key questions: 1. What properties should be characterised for nanomaterials used in environmental and ecotoxicology studies? 2. What reference materials should be developed for use in environmental and ecotoxicological studies? 3. Is it possible to group different nanomaterials into categories for consideration in environmental studies? Such questions have been, at least partially, addressed by other projects/workshops especially in relation to human health effects. Such projects provide a useful basis on which this workshop was based, but in this particular case these questions were reformulated in order to focus specifically on environmental studies. The workshop participants, through a series of discussion and reflection sessions, generated the conclusions listed below. The physicochemical characterisation information identified as important for environmental studies included measures of aggregation/agglomeration/dispersability, size, dissolution (solubility), surface area, surface charge, surface chemistry/composition, with the assumption that chemical composition would already be known. There is a need to have test materials for ecotoxicology, and several substances are potentially useful, including TiO(2) nanoparticles, polystyrene beads labelled with fluorescent dyes, and silver nanoparticles. Some of these test materials could then be developed into certified reference materials over time. No clear consensus was reached regarding the classification of nanomaterials into categories to aid environmental studies, except that a chemistry-based classification system was a reasonable starting point, with some modifications. It was suggested, that additional work may be

  5. 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.

  6. 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.

  7. 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.

  8. Identification and quantitation of arsenic species in a dogfish muscle reference material for trace elements

    SciTech Connect

    Beauchemin, D.; Bednas, M.E.; Berman, S.S.; McLaren, J.W.; Siu, K.W.M.; Sturgeon, R.E.

    1988-10-15

    The arsenic species present in a dogfish muscle reference material (DORM-1) have been identified by using high-performance liquid chromatography/inductively coupled plasma mass spectrometry (HPLC/ICP-MS), thin-layer chromatography, and electron impact mass spectrometry and quantified by using HPLC/ICP-MS and graphite furnace atomic absorption spectrometry. The major species is arsenobetaine (15.7 +/- 0.8 ..mu..g of As/g of DORM-1), constituting about 84% of the total arsenic. For this species, the HPLC/ICP-MS detection limit was 0.3 ng of As.

  9. International Standards and Reference Materials for Quantitative Molecular Infectious Disease Testing

    PubMed Central

    Madej, Roberta M.; Davis, Jack; Holden, Marcia J.; Kwang, Stan; Labourier, Emmanuel; Schneider, George J.

    2010-01-01

    The utility of quantitative molecular diagnostics for patient management depends on the ability to relate patient results to prior results or to absolute values in clinical practice guidelines. To do this, those results need to be comparable across time and methods, either by producing the same value across methods and test versions or by using reliable and stable conversions. Universally available standards and reference materials specific to quantitative molecular technologies are critical to this process but are few in number. This review describes recent history in the establishment of international standards for nucleic acid test development, organizations involved in current efforts, and future issues and initiatives. PMID:20075208

  10. International standards and reference materials for quantitative molecular infectious disease testing.

    PubMed

    Madej, Roberta M; Davis, Jack; Holden, Marcia J; Kwang, Stan; Labourier, Emmanuel; Schneider, George J

    2010-03-01

    The utility of quantitative molecular diagnostics for patient management depends on the ability to relate patient results to prior results or to absolute values in clinical practice guidelines. To do this, those results need to be comparable across time and methods, either by producing the same value across methods and test versions or by using reliable and stable conversions. Universally available standards and reference materials specific to quantitative molecular technologies are critical to this process but are few in number. This review describes recent history in the establishment of international standards for nucleic acid test development, organizations involved in current efforts, and future issues and initiatives.

  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. 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.

  13. The certification of cocaine and benzoylecgonine in a human urine standard reference material.

    PubMed

    Ellerbe, P; Tai, S S; Christensen, R G; Espinosa-Leniz, R; Paule, R C; Sander, L C; Sniegoski, L T; Welch, M J; White, E

    1992-01-01

    The concentrations of cocaine and benzoylecgonine (BE) in Standard Reference Material (SRM) 1508, cocaine and metabolites in freeze-dried human urine, were determined at the National Institute of Standards and Technology (NIST, formerly NBS) by two independent methods. For cocaine, one method was based on gas chromatography/mass spectrometry (GC/MS); the other was based on high-performance liquid chromatography (HPLC). For BE, one method was based on GC/MS; the other was based on flow injection analysis/thermospray mass spectrometry (FIA/MS). The results for each pair of methods were statistically evaluated. Concentrations were determined in the SRM for three levels of cocaine and three levels of benzoylecgonine. Methylecgonine, although present in the material, was not determined. For cocaine, the concentrations were 90, 263, and 429 ng/mL of human urine. For BE, the concentrations were 103, 259, and 510 ng/mL of human urine.

  14. Role of chromatography in the development of Standard Reference Materials for organic analysis.

    PubMed

    Wise, Stephen A; Phinney, Karen W; Sander, Lane C; Schantz, Michele M

    2012-10-26

    The certification of chemical constituents in natural-matrix Standard Reference Materials (SRMs) at the National Institute of Standards and Technology (NIST) can require the use of two or more independent analytical methods. The independence among the methods is generally achieved by taking advantage of differences in extraction, separation, and detection selectivity. This review describes the development of the independent analytical methods approach at NIST, and its implementation in the measurement of organic constituents such as contaminants in environmental materials, nutrients and marker compounds in food and dietary supplement matrices, and health diagnostic and nutritional assessment markers in human serum. The focus of this review is the important and critical role that separation science techniques play in achieving the necessary independence of the analytical steps in the measurement of trace-level organic constituents in natural matrix SRMs.

  15. The certification of morphine and codeine in a human urine standard reference material.

    PubMed

    Tai, S S; Christensen, R G; Paule, R C; Sander, L C; Welch, M J

    1994-01-01

    The National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards) has developed and certified a Standard Reference Material, SRM 2381, for use in testing for bias in determinations of morphine and codeine in human urine. Each unit of this SRM consists of three vials with different levels of morphine and codeine in lyophilized urine. Three different analytical methods, employing GC/MS, LC/MS, and MS/MS, were used to certify the concentrations of each analyte. Results from the three methods were in good agreement and, therefore, were statistically combined to yield certified values of 138, 293, and 578 ng/mL for morphine and 134, 283, and 591 for codeine. A round-robin study on this material among nine military laboratories demonstrated the suitability of the SRM for its intended purpose.

  16. 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.

  17. Production and certification of NIST Standard Reference Material 2372 Human DNA Quantitation Standard.

    PubMed

    Kline, Margaret C; Duewer, David L; Travis, John C; Smith, Melody V; Redman, Janette W; Vallone, Peter M; Decker, Amy E; Butler, John M

    2009-06-01

    Modern highly multiplexed short tandem repeat (STR) assays used by the forensic human-identity community require tight control of the initial amount of sample DNA amplified in the polymerase chain reaction (PCR) process. This, in turn, requires the ability to reproducibly measure the concentration of human DNA, [DNA], in a sample extract. Quantitative PCR (qPCR) techniques can determine the number of intact stretches of DNA of specified nucleotide sequence in an extremely small sample; however, these assays must be calibrated with DNA extracts of well-characterized and stable composition. By 2004, studies coordinated by or reported to the National Institute of Standards and Technology (NIST) indicated that a well-characterized, stable human DNA quantitation certified reference material (CRM) could help the forensic community reduce within- and among-laboratory quantitation variability. To ensure that the stability of such a quantitation standard can be monitored and that, if and when required, equivalent replacement materials can be prepared, a measurement of some stable quantity directly related to [DNA] is required. Using a long-established conventional relationship linking optical density (properly designated as decadic attenuance) at 260 nm with [DNA] in aqueous solution, NIST Standard Reference Material (SRM) 2372 Human DNA Quantitation Standard was issued in October 2007. This SRM consists of three quite different DNA extracts: a single-source male, a multiple-source female, and a mixture of male and female sources. All three SRM components have very similar optical densities, and thus very similar conventional [DNA]. The materials perform very similarly in several widely used gender-neutral assays, demonstrating that the combination of appropriate preparation methods and metrologically sound spectrophotometric measurements enables the preparation and certification of quantitation [DNA] standards that are both maintainable and of practical utility.

  18. Certified DNA Reference Materials to Compare HER2 Gene Amplification Measurements Using Next-Generation Sequencing Methods.

    PubMed

    Lih, Chih-Jian; Si, Han; Das, Biswajit; Harrington, Robin D; Harper, Kneshay N; Sims, David J; McGregor, Paul M; Camalier, Corinne E; Kayserian, Andrew Y; Williams, P Mickey; He, Hua-Jun; Almeida, Jamie L; Lund, Steve P; Choquette, Steve; Cole, Kenneth D

    2016-09-01

    The National Institute of Standards and Technology (NIST) Standard Reference Materials 2373 is a set of genomic DNA samples prepared from five breast cancer cell lines with certified values for the ratio of the HER2 gene copy number to the copy numbers of reference genes determined by real-time quantitative PCR and digital PCR. Targeted-amplicon, whole-exome, and whole-genome sequencing measurements were used with the reference material to compare the performance of both the laboratory steps and the bioinformatic approaches of the different methods using a range of amplification ratios. Although good reproducibility was observed in each next-generation sequencing method, slightly different HER2 copy numbers associated with platform-specific biases were obtained. This study clearly demonstrates the value of Standard Reference Materials 2373 as reference material and as a calibrator for evaluating assay performance as well as for increasing confidence in reporting HER2 amplification for clinical applications.

  19. NIST High Resolution X-Ray Diffraction Standard Reference Material: SRM 2000

    NASA Astrophysics Data System (ADS)

    Windover, Donald; Gil, David L.; Henins, Albert; Cline, James P.

    2009-09-01

    NIST recently released a standard reference material (SRM) for the calibration of high resolution X-ray diffraction (HRXRD) instruments. HRXRD is extensively used in the characterization of lattice distortion in thin single, epitaxial crystal layers on single-crystal wafer substrates. Currently, there is a great need for improved accuracy and transferability for the measurement of strain fields in these epitaxial thin films. This implies an essential need for the calibration of HRXRD instruments to allow measurement intercomparison for both research and manufacturing communities. This first HRXRD SRM release provides certified measurements of diffraction features for a silicon reference substrate, Si (220) in transmission and Si (004) in reflection, allowing for calibration of either monochromator wavelength or goniometer angles. The SRM also provides information on the surface-to-crystal-plane misalignment, which allows calibration of sample holders and sample alignment hardware. This calibration should reduce the uncertainties when comparing, for instance, reciprocal space maps. Here we present a detailed description of these measured values and provide methods for using these to calibrate HRXRD instrumentation. SRM 2000 provides the semiconductor and the larger nanoscience community with the first nanometer length-scale reference standard with femtometer accuracy; the Si (220) transmission-feature-derived silicon lattice spacing, dSRM, has a value of 0.1920161 nm with an expanded uncertainty, U (dSRM), of 0.87 fm.

  20. 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.

  1. Development and application of a general plasmid reference material for GMO screening.

    PubMed

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

    The use of analytical controls is essential when performing GMO detection through screening tests. Additionally, the presence of taxon-specific sequences is analyzed mostly for quality control during GMO detection. In this study, 11 commonly used genetic elements involving three promoters (P-35S, P-FMV35S and P-NOS), four marker genes (Bar, NPTII, HPT and Pmi), and four terminators (T-NOS, T-35S, T-g7 and T-e9), together with the reference gene fragments from six major crops of maize, soybean, rapeseed, rice, cotton and wheat, were co-integrated into the same single plasmid to construct a general reference plasmid pBI121-Screening. The suitability test of pBI121-Screening plasmid as reference material indicated that the non-target sequence on the pBI121-Screening plasmid did not affect the PCR amplification efficiencies of screening methods and taxon-specific methods. The sensitivity of screening and taxon-specific assays ranged from 5 to 10 copies of pBI121-Screening plasmid, meeting the sensitivity requirement of GMO detection. The construction of pBI121-Screening solves the lack of a general positive control for screening tests, thereby reducing the workload and cost of preparing a plurality of the positive control.

  2. Acoustic mapping of the regional seafloor geology in and around Hawaiian ocean dredged-material disposal sites

    USGS Publications Warehouse

    Torresan, Michael E.; Gardner, James V.

    2000-01-01

    During January and February 1998 the U.S. Geological Survey Coastal and Marine Geology Team (USGS) conducted regional high-resolution multibeam mapping surveys of the area surrounding EPA-designated ocean disposal sites located offshore of the Hawaiian Islands of Oahu, Kauai, Maui, and Hawaii. The sites are all located within 5 nautical miles of shore on insular shelves or slopes. Regional maps were required of areas much larger than the disposal sites themselves to assess both the regional seafloor geology and the immediate vicinity of the disposal sites. The purpose of the disposal site surveys was to delimit the extent of disposal material by producing detailed bathymetric and backscatter maps of the seafloor with a ± 1 m spatial accuracy and <1% depth error. The advantage of using multibeam over conventional towed, single-beam sidescan sonar is that the multibeam data are accurately georeferenced for precise location of all imaged features. The multibeam produces a coregistered acoustic-backscatter map that is often required to locate individual disposal deposits. These data were collected by the USGS as part of its regional seafloor mapping and in support of ocean disposal site monitoring studies conducted in cooperation with the US Environmental Protection Agency (EPA) and the US Army Corps of Engineers (COE).

  3. 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.

  4. 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

  5. Characterization of perchlorate in a new frozen human urine standard reference material.

    PubMed

    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

    2012-10-01

    Perchlorate, an inorganic anion, has recently been recognized as an environmental contaminant by the US Environmental Protection Agency. 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. 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 US 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. 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 ± 0.21 μg L(-1), and for SRM 3668 Level II urine, the certified value is 13.47 ± 0.96 μg L(-1).

  6. 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.

  7. Conservation of phage reference materials and water samples containing bacteriophages of enteric bacteria.

    PubMed

    Mendez, J; Jofre, J; Lucena, F; Contreras, N; Mooijman, K; Araujo, R

    2002-12-01

    The survival was determined in different conservation conditions of: somatic coliphages, F-specific RNA bacteriophages and phages infecting Bacteroides fragilis proposed as model micro-organisms for water quality control. Titres of phages of all groups either in pure culture phage suspensions or in naturally occurring phage suspensions were stable at (-70+/-10) degrees C and at (-20+/-5) degrees C when protected with glycerol. Moreover, phage analysis of stored suspensions demonstrated that their numbers were homogeneous, both between vials and within vials, and consequently they can be used as reference materials. Furthermore, changes in the storage temperature of the vials cause unpredictable changes in the numbers of bacteriophages. Consequently, phage reference materials and samples containing a quantitative number of phages must be maintained and dispatched at a constant temperature. Consequently, the results indicate that bacteriophages should be packed in dry ice during transport and storage. Finally, the number of phages in water samples stored at (5+/-3) degrees C in the dark does not decrease significantly during the first 72 h of storage. In addition, phage concentrates from natural samples obtained by adsorption-elution to cellulose nitrate filters and mixed with 10% glycerol were stable at least for 2 months at (-70+/-10) degrees C and at (-20+/-5) degrees C.

  8. In Vitro Investigations of Human Bioaccessibility from Reference Materials Using Simulated Lung Fluids

    PubMed Central

    Pelfrêne, Aurélie; Cave, Mark R.; Wragg, Joanna; Douay, Francis

    2017-01-01

    An investigation for assessing pulmonary bioaccessibility of metals from reference materials is presented using simulated lung fluids. The objective of this paper was to contribute to an enhanced understanding of airborne particulate matter and its toxic potential following inhalation. A large set of metallic elements (Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, and Zn) was investigated using three lung fluids (phosphate-buffered saline, Gamble’s solution and artificial lysosomal fluid) on three standard reference materials representing different types of particle sources. Composition of the leaching solution and four solid-to-liquid (S/L) ratios were tested. The results showed that bioaccessibility was speciation- (i.e., distribution) and element-dependent, with percentages varying from 0.04% for Pb to 86.0% for Cd. The higher extraction of metallic elements was obtained with the artificial lysosomal fluid, in which a relative stability of bioaccessibility was observed in a large range of S/L ratios from 1/1000 to 1/10,000. For further investigations, it is suggested that this method be used to assess lung bioaccessibility of metals from smelter-impacted dusts. PMID:28125027

  9. Development of a matrix-based candidate reference material of total homocysteine in human serum.

    PubMed

    Liu, Yu; Song, Dewei; Xu, Bei; Li, Hongmei; Dai, Xinhua; Chen, Baorong

    2017-03-07

    We developed and evaluated a candidate serum reference material to help improve clinical routine measurement, and to provide traceability of the measurement results. D8-Homocystine, dithiothreitol, and acetonitrile were used as an internal standard, the reducing agent, and the protein precipitating agent, respectively. A triple quadrupole mass spectrometer with an electrospray ionization source was used for monitoring the transitions (m/z 140.0 → 94.0, 136.0 → 90.0) in multiple-reaction-monitoring mode. We used a calibration model relying on bracketing and gravimetric measurements to give SI-traceability and higher accuracy to serum value assignments. The method was evaluated for accuracy using NIST Standard Reference Material SRM1955. The results of the three concentrations (1, 2, and 3) of total homocysteine in human serum samples were determined by an isotope-dilution liquid chromatography-tandem mass spectrometry method; tHcy 1 is 28.8 ± 1.1 μmol/L, tHcy 2 is 17.93 ± 0.57 μmol/L, and tHcy 3 is 14.38 ± 0.46 μmol/L. Graphical abstract The workflow diagram.

  10. Palm-based standard reference materials for iodine value and slip melting point.

    PubMed

    Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai; Kuntom, Ainie

    2008-09-22

    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 degrees C in palm oil, 22.7 +/- 0.4 degrees C in palm olein and 53.4 +/- 0.2 degrees 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 degrees C, 0 degrees C, 6 degrees C and 24 degrees C upon storage for one year.

  11. 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.

  12. Preparation and certification of arsenate [As(V)] reference material, NMIJ CRM 7912-a.

    PubMed

    Narukawa, Tomohiro; Kuroiwa, Takayoshi; Narushima, Izumi; Jimbo, Yasujiro; Suzuki, Toshihiro; Chiba, Koichi

    2010-05-01

    Arsenate [As(V)] solution reference material, National Metrology Institute of Japan (NMIJ) certified reference material (CRM) 7912-a, for speciation of arsenic species was developed and certified by NMIJ, the National Institute of Advanced Industrial Science and Technology. High-purity As(2)O(3) reagent powder was dissolved in 0.8 M HNO(3) solution and As(III) was oxidized to As(V) with HNO(3) to prepare 100 mg kg(-1) of As(V) candidate CRM solution. The solution was bottled in 400 bottles (50 mL each). The concentration of As(V) was determined by four independent analytical techniques-inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectrometry, graphite furnace atomic absorption spectrometry, and liquid chromatography inductively coupled plasma mass spectrometry-according to As(V) calibration solutions, which were prepared from the arsenic standard of the Japan Calibration Service system and whose species was guaranteed to be As(V) by NMIJ. The uncertainties of all the measurements and preparation procedures were evaluated. The certified value of As(V) in the CRM is (99.53 +/- 1.67) mg kg(-1) (k = 2).

  13. Applications of a New Handheld Reference Point Indentation Instrument Measuring Bone Material Strength.

    PubMed

    Randall, Connor; Bridges, Daniel; Guerri, Roberto; Nogues, Xavier; Puig, Lluis; Torres, Elisa; Mellibovsky, Leonardo; Hoffseth, Kevin; Stalbaum, Tyler; Srikanth, Ananya; Weaver, James C; Rosen, Sasha; Barnard, Heather; Brimer, Davis; Proctor, Alex; Candy, James; Saldana, Christopher; Chandrasekar, Srinivasan; Lescun, Timothy; Nielson, Carrie M; Orwoll, Eric; Herthel, Doug; Kopeikin, Hal; Yang, Henry T Y; Farr, Joshua N; McCready, Louise; Khosla, Sundeep; Diez-Perez, Adolfo; Hansma, Paul K

    2013-12-01

    A novel, hand-held Reference Point Indentation (RPI) instrument, measures how well the bone of living patients and large animals resists indentation. The results presented here are reported in terms of Bone Material Strength, which is a normalized measure of how well the bone resists indentation, and is inversely related to the indentation distance into the bone. We present examples of the instrument's use in: (1) laboratory experiments on bone, including experiments through a layer of soft tissue, (2) three human clinical trials, two ongoing in Barcelona and at the Mayo Clinic, and one completed in Portland, OR, and (3) two ongoing horse clinical trials, one at Purdue University and another at Alamo Pintado Stables in California. The instrument is capable of measuring consistent values when testing through soft tissue such as skin and periosteum, and does so handheld, an improvement over previous Reference Point Indentation instruments. Measurements conducted on horses showed reproducible results when testing the horse through tissue or on bare bone. In the human clinical trials, reasonable and consistent values were obtained, suggesting the Osteoprobe(®) is capable of measuring Bone Material Strength in vivo, but larger studies are needed to determine the efficacy of the instrument's use in medical diagnosis.

  14. 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.

  15. Distribution of materials excavated by the lunar crater Bullialdus and implications for the geologic history of the Nubium region

    NASA Astrophysics Data System (ADS)

    Tompkins, Stefanie; Pieters, Carle M.; Mustard, John F.; Pinet, Patrick; Chevrel, Serge D.

    1994-08-01

    Previous spectroscopic studies of the lunar crater Bullialdus, located in the Nubium Basin, indicated an unusual stratigraphy of two gabbroic layers overlying a noritic unit. The possible existence of a layered mafic pluton at Bullialdus was suggested. To investigate the geologic context with more detailed spatial information, charge-coupled device (CCD) images of Bullialdus were obtained using eight filters. A linear mixing model was used to investigate the fractional abundances of spectral end-members chosen from within the multispectral image. Since the reflectance properties of lunar materials over this wavelength range are sensitive to variations in composition and soil maturity, fractional abundance images were used to create a new geologic map of the crater. The spatial relationships of the surface materials confirm the previously inferred stratigraphy, and further reveal the central peaks to exhibit two distinct compositional units: noritic anorthosite and anorthositic norite. Three models for the origin of the observed stratigraphy are considered: Bullialdus has excavated stratigraphic units containing (1) early mare basalt overlying anorthositic-noritic crustal material, (2) part of a layered mafic pluton, and/or (3) part of an impact melt sheet formed by the Nubium Basin impact event.

  16. 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.

  17. A reference material with close to Lambertian reflectance and fluorescence emission profiles

    NASA Astrophysics Data System (ADS)

    Jaanson, P.; Pulli, T.; Manoocheri, F.; Ikonen, E.

    2016-12-01

    Fluorescent brightening agents are widely used in various industries to enhance the appearance of materials. The angular profiles of emission and reflectance of fluorescent surfaces have been shown to deviate from Lambertian behaviour, however, in industry and calibration facilities single geometry measurements are often used, which requires assumptions to be made on the angular distributions. In addition, the angular distribution of reflectance has been shown to deviate from that of fluorescence. In this work, it is shown that the angular distribution of reflectance is dependent on the excitation wavelength and the effect is explained by qualitative and quantitative models. These angular and spectral effects may cause measurement errors when single geometry bidirectional measurements are carried out. The angular distributions can be taken into account by using goniometrical measurements, which however, result in increased calibration time and cost. Alternatively, a reference material could be used where the angular dependencies are minimised. In this work, a novel material is presented which demonstrates more Lambertian emission and reflectance profiles than conventional polytetrafluoroethylene (PTFE) based materials and a smaller dependence of angular reflectance on the absorbance of the sample.

  18. Characterization of NIST food-matrix Standard Reference Materials for their vitamin C content.

    PubMed

    Thomas, Jeanice B; Yen, James H; Sharpless, Katherine E

    2013-05-01

    The vitamin C concentrations in three food-matrix Standard Reference Materials (SRMs) from the National Institute of Standards and Technology (NIST) have been determined by liquid chromatography (LC) with absorbance detection. These materials (SRM 1549a Whole Milk Powder, SRM 1849a Infant/Adult Nutritional Formula, and SRM 3233 Fortified Breakfast Cereal) have been characterized to support analytical measurements made by food processors that are required to provide information about their products' vitamin C content on the labels of products distributed in the United States. The SRMs are primarily intended for use in validating analytical methods for the determination of selected vitamins, elements, fatty acids, and other nutrients in these materials and in similar matrixes. They can also be used for quality assurance in the characterization of test samples or in-house control materials, and for establishing measurement traceability. Within-day precision of the LC method used to measure vitamin C in the food-matrix SRMs characterized in this study ranged from 2.7% to 6.5%.

  19. Geological Gyrocompass

    NASA Astrophysics Data System (ADS)

    McKeown, M. H.; Beason, S. C.

    1990-10-01

    The invention relates to a new and improved geologic mapping and surveying apparatus for providing accurate, dependable, and portable measurement of attitudes of planar surfaces in situations where magnetic compasses will not work. The invention provides a unique arrangement of the gyrocompass and power supply in a portable carrying case. A gyroscope is not dependent on the earth's magnetic field for a reference as is a magnetic compass. Therefore, the invention of a geological gyrocompass is immune to disturbances in the earth's magnetic field and nearly duplicates the Brunton compass accuracy but does not require an environment free of magnetic anomalies.

  20. Sets of spectral lines for spectrographic thermometry and manometry in d.c. arcs of geologic materials

    USGS Publications Warehouse

    Golightly, D.W.; Dorrzapf, A.F.; Thomas, C.P.

    1977-01-01

    Sets of 5 Fe(I) lines and 3 Ti(I)Ti(II) line pairs have been characterized for precise spectrographic thermometry and manometry, respectively, in d.c. arcs of geologic materials. The recommended lines are free of spectral interferences, exhibit minimal self absorption within defined concentration intervals, and are useful for chemically-unaltered silicate rocks, arced in an argon-oxygen stream. The functional character of these lines in thermometry and manometry of d.c. arcs for evaluations of electrical parameter effects, for temporal studies, and for matrix-effect investigations on real samples is illustrated. ?? 1977.

  1. Nanoscale reference materials for environmental, health and safety measurements: needs, gaps and opportunities.

    PubMed

    Stefaniak, Aleksandr B; Hackley, Vincent A; Roebben, Gert; Ehara, Kensei; Hankin, Steve; Postek, Michael T; Lynch, Iseult; Fu, Wei-En; Linsinger, Thomas P J; Thünemann, Andreas F

    2013-12-01

    The authors critically reviewed published lists of nano-objects and their physico-chemical properties deemed important for risk assessment and discussed metrological challenges associated with the development of nanoscale reference materials (RMs). Five lists were identified that contained 25 (classes of) nano-objects; only four (gold, silicon dioxide, silver, titanium dioxide) appeared on all lists. Twenty-three properties were identified for characterisation; only (specific) surface area appeared on all lists. The key themes that emerged from this review were: 1) various groups have prioritised nano-objects for development as "candidate RMs" with limited consensus; 2) a lack of harmonised terminology hinders accurate description of many nano-object properties; 3) many properties identified for characterisation are ill-defined or qualitative and hence are not metrologically traceable; 4) standardised protocols are critically needed for characterisation of nano-objects as delivered in relevant media and as administered to toxicological models; 5) the measurement processes being used to characterise a nano-object must be understood because instruments may measure a given sample in a different way; 6) appropriate RMs should be used for both accurate instrument calibration and for more general testing purposes (e.g., protocol validation); 7) there is a need to clarify that where RMs are not available, if "(representative) test materials" that lack reference or certified values may be useful for toxicology testing and 8) there is a need for consensus building within the nanotechnology and environmental, health and safety communities to prioritise RM needs and better define the required properties and (physical or chemical) forms of the candidate materials.

  2. USGS42 and USGS43: Human-hair stable hydrogen and oxygen isotopic reference materials and analytical methods for forensic science and implications for published measurement results

    USGS Publications Warehouse

    Coplen, T.B.; Qi, H.

    2012-01-01

    Because there are no internationally distributed stable hydrogen and oxygen isotopic reference materials of human hair, the U.S. Geological Survey (USGS) has prepared two such materials, USGS42 and USGS43. These reference materials span values commonly encountered in human hair stable isotope analysis and are isotopically homogeneous at sample sizes larger than 0.2 mg. USGS42 and USGS43 human-hair isotopic reference materials are intended for calibration of δ(2)H and δ(18)O measurements of unknown human hair by quantifying (1) drift with time, (2) mass-dependent isotopic fractionation, and (3) isotope-ratio-scale contraction. While they are intended for measurements of the stable isotopes of hydrogen and oxygen, they also are suitable for measurements of the stable isotopes of carbon, nitrogen, and sulfur in human and mammalian hair. Preliminary isotopic compositions of the non-exchangeable fractions of these materials are USGS42(Tibetan hair)δ(2)H(VSMOW-SLAP) = -78.5 ± 2.3‰ (n = 62) and δ(18)O(VSMOW-SLAP) = +8.56 ± 0.10‰ (n = 18) USGS42(Indian hair)δ(2)H(VSMOW-SLAP) = -50.3 ± 2.8‰ (n = 64) and δ(18)O(VSMOW-SLAP) = +14.11 ± 0.10‰ (n = 18). Using recommended analytical protocols presented herein for δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) measurements, the least squares fit regression of 11 human hair reference materials is δ(2)H(VSMOW-SLAP) = 6.085δ(2)O(VSMOW-SLAP) - 136.0‰ with an R-square value of 0.95. The δ(2)H difference between the calibrated results of human hair in this investigation and a commonly accepted human-hair relationship is a remarkable 34‰. It is critical that readers pay attention to the δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) of isotopic reference materials in publications, and they need to adjust the δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) measurement results of human hair in previous publications, as needed, to ensure all results on are on the same scales.

  3. USGS42 and USGS43: human-hair stable hydrogen and oxygen isotopic reference materials and analytical methods for forensic science and implications for published measurement results.

    PubMed

    Coplen, Tyler B; Qi, Haiping

    2012-01-10

    Because there are no internationally distributed stable hydrogen and oxygen isotopic reference materials of human hair, the U.S. Geological Survey (USGS) has prepared two such materials, USGS42 and USGS43. These reference materials span values commonly encountered in human hair stable isotope analysis and are isotopically homogeneous at sample sizes larger than 0.2 mg. USGS42 and USGS43 human-hair isotopic reference materials are intended for calibration of δ(2)H and δ(18)O measurements of unknown human hair by quantifying (1) drift with time, (2) mass-dependent isotopic fractionation, and (3) isotope-ratio-scale contraction. While they are intended for measurements of the stable isotopes of hydrogen and oxygen, they also are suitable for measurements of the stable isotopes of carbon, nitrogen, and sulfur in human and mammalian hair. Preliminary isotopic compositions of the non-exchangeable fractions of these materials are USGS42(Tibetan hair)δ(2)H(VSMOW-SLAP) = -78.5 ± 2.3‰ (n = 62) and δ(18)O(VSMOW-SLAP) = +8.56 ± 0.10‰ (n = 18) USGS42(Indian hair)δ(2)H(VSMOW-SLAP) = -50.3 ± 2.8‰ (n = 64) and δ(18)O(VSMOW-SLAP) = +14.11 ± 0.10‰ (n = 18). Using recommended analytical protocols presented herein for δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) measurements, the least squares fit regression of 11 human hair reference materials is δ(2)H(VSMOW-SLAP) = 6.085δ(2)O(VSMOW-SLAP) - 136.0‰ with an R-square value of 0.95. The δ(2)H difference between the calibrated results of human hair in this investigation and a commonly accepted human-hair relationship is a remarkable 34‰. It is critical that readers pay attention to the δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) of isotopic reference materials in publications, and they need to adjust the δ(2)H(VSMOW-SLAP) and δ(18)O(VSMOW-SLAP) measurement results of human hair in previous publications, as needed, to ensure all results on are on the same scales.

  4. Testing for fullerenes in geologic materials: Oklo carbonaceous substances, Karelian shungites, Sudbury Black Tuff

    NASA Astrophysics Data System (ADS)

    Mossman, David; Eigendorf, Guenter; Tokaryk, Dennis; Gauthier-Lafaye, François; Guckert, Kristal D.; Melezhik, Victor; Farrow, Catharine E. G.

    2003-03-01

    Fullerenes have been reported from diverse geologic environments since their discovery in shungite from Karelian Russia. Our investigation is prompted by the presence of onionskin-like structures in some carbonaceous substances associated with the fossil nuclear fission reactors of Oklo, Gabon. The same series of extractions and the same instrumental techniques, laser desorption ionization and high-resolution mass spectroscopy (electron-impact mass spectroscopy), were employed to test for fullerenes in samples from three different localities: two sites containing putative fullerenes (Sudbury Basin and Russian Karelia) and one new location (Oklo, Gabon). We confirm the presence of fullerenes (C60 and C70) in the Black Tuff of the Onaping Formation impact breccia in the Sudbury Basin, but we find no evidence of fullerenes in shungite samples from various locations in Russian Karelia. Analysis of carbonaceous substances associated with the natural nuclear fission reactors of Oklo yields no definitive signals for fullerenes. If fullerenes were produced during sustained nuclear fission at Oklo, then they are present below the detection limit (˜100 fmol), or they have destabilized since formation. Contrary to some expectations, geologic occurrences of fullerenes are not commonplace.

  5. Distribution and geological sources of selenium in environmental materials in Taoyuan County, Hunan Province, China.

    PubMed

    Ni, Runxiang; Luo, Kunli; Tian, Xinglei; Yan, Songgui; Zhong, Jitai; Liu, Maoqiu

    2016-06-01

    The selenium (Se) distribution and geological sources in Taoyuan County, China, were determined by using hydride generation atomic fluorescence spectrometry on rock, soil, and food crop samples collected from various geological regions within the county. The results show Se contents of 0.02-223.85, 0.18-7.05, and 0.006-5.374 mg/kg in the rock, soil, and food crops in Taoyuan County, respectively. The region showing the highest Se content is western Taoyuan County amid the Lower Cambrian and Ediacaran black rock series outcrop, which has banding distributed west to east. A relatively high-Se environment is found in the central and southern areas of Taoyuan County, where Quaternary Limnetic sedimentary facies and Neoproterozoic metamorphic volcanic rocks outcrop, respectively. A relatively low-Se environment includes the central and northern areas of Taoyuan County, where Middle and Upper Cambrian and Ordovician carbonate rocks and Cretaceous sandstones and conglomerates outcrop. These results indicate that Se distribution in Taoyuan County varies markedly and is controlled by the Se content of the bedrock. The Se-enriched Lower Cambrian and Ediacaran black rock series is the primary source of the seleniferous environment observed in Taoyuan County. Potential seleniferous environments are likely to be found near outcrops of the Lower Cambrian and Ediacaran black rock series in southern China.

  6. Simulations of Fracture and Fragmentation of Geologic Materials using Combined FEM/DEM Analysis

    SciTech Connect

    Morris, J P; Rubin, M B; Block, G I; Bonner, M P

    2005-05-26

    Results are presented from a study investigating the effect of explosive and impact loading on geological media using the Livermore Distinct Element Code (LDEC). LDEC was initially developed to simulate tunnels and other structures in jointed rock masses with large numbers of intact polyhedral blocks. However, underground structures in jointed rock subjected to explosive loading can fail due to both rock motion along preexisting interfaces and fracture of the intact rock mass itself. Many geophysical applications, such as projectile penetration into rock, concrete targets, and boulder fields, require a combination of continuum and discrete methods in order to predict the formation and interaction of the fragments produced. In an effort to model these types of problems, we have implemented Cosserat point theory and cohesive element formulations into the current version of LDEC, thereby allowing for dynamic fracture and combined finite element/discrete element simulations. Results of a large-scale LLNL simulation of an explosive shock wave impacting an elaborate underground facility are also discussed. It is confirmed that persistent joints lead to an underestimation of the impact energy needed to fill the tunnel systems with rubble. Non-persistent joint patterns, which are typical of real geologies, inhibit shear within the surrounding rock mass and significantly increase the load required to collapse a tunnel.

  7. Characterizing Vaccinium berry Standard Reference Materials by GC-MS using NIST spectral libraries.

    PubMed

    Lowenthal, Mark S; Andriamaharavo, Nirina R; Stein, Stephen E; Phinney, Karen W

    2013-05-01

    A gas chromatography-mass spectrometry (GC-MS)-based method was developed for qualitative characterization of metabolites found in Vaccinium fruit (berry) dietary supplement Standard Reference Materials (SRMs). Definitive identifications are provided for 98 unique metabolites determined among six Vaccinium-related SRMs. Metabolites were enriched using an organic liquid/liquid extraction, and derivatized prior to GC-MS analysis. Electron ionization (EI) fragmentation spectra were searched against EI spectra of authentic standards compiled in the National Institute of Standards and Technology's mass spectral libraries, as well as spectra selected from the literature. Metabolite identifications were further validated using a retention index match along with prior probabilities and were compared with results obtained in a previous effort using collision-induced dissociation (CID) MS/MS datasets from liquid chromatography coupled to mass spectrometry experiments. This manuscript describes a nontargeted metabolite profile of Vaccinium materials, compares results among related materials and from orthogonal experimental platforms, and discusses the feasibility and development of using mass spectral library matching for nontargeted metabolite identification.

  8. Quaternary geologic map of Minnesota

    NASA Technical Reports Server (NTRS)

    Goebel, J. E.

    1977-01-01

    The Quaternary Geologic Map of Minnesota is a compilation based both on the unique characteristics of satellite imagery and on the results of previous field investigations, both published and unpublished. The use of satellite imagery has made possible the timely and economical construction of this map. LANDSAT imagery interpretation proved more useful than expected. Most of the geologic units could be identified by extrapolating from specific sites where the geology had been investigated into areas where little was known. The excellent geographic registry coupled with the multi-spectral record of these images served to identify places where the geologic materials responded to their ecological environment and where the ecology responded to the geologic materials. Units were well located on the map at the scale selected for the study. Contacts between till units could be placed with reasonable accuracy. The reference points that were used to project delineations between units (rivers, lakes, hills, roads and other features), which had not been accurately located on early maps, could be accurately located with the help of the imagery. The tonal and color contrasts, the patterns reflecting geologic change and the resolution of the images permitted focusing attention on features which could be represented at the final scale of the map without distraction by other interesting but site-specific details.

  9. Spatial Distribution of Uranium in Groundwater and Associated Geologic Material at the NABIR Field Research Center Site, Oak Ridge, Tennessee

    NASA Astrophysics Data System (ADS)

    Phillips, D. H.; Watson, D. B.

    2001-05-01

    The Natural and Accelerated Bioremediation Research Program (NABIR) has established a Field Research Center (FRC) on the Oak Ridge Reservation in Oak Ridge, Tennessee. The FRC provides a site for investigators to conduct research and obtain samples related to in situ bioremediation. This site is in the form of four buried unlined ponds where uranium and other contaminants were disposed in nitric acid for 32 years. In 1984, the ponds were neutralized with limestone, RCRA capped and paved with a parking lot. Analysis of groundwater and geologic material sampled from the site show that uranium is preferentially migrating away from the ponds and towards the nearby Bear Creek. Preferential flow appears to be associated with an ancient buried stream bed and remnant fractures in the saprolite where the uranium content of the groundwater is as high as 7 ppm. Due to the greater discharge of the contaminant source in this portion of the regolith, there is higher weathering of the shallow regolith (top 20 ft)and a greater accumulation of uranium compared to other sections of geologic material surrounding the disposal site.

  10. Determination of indium in geological materials by electrothermal-atomization atomic absorption spectrometry with a tungsten-impregnated graphite furance

    USGS Publications Warehouse

    Zhou, L.; Chao, T.T.; Meier, A.L.

    1984-01-01

    The sample is fused with lithium metaborate and the melt is dissolved in 15% (v/v) hydrobromic acid. Iron(III) is reduced with ascorbic acid to avoid its coextraction with indium as the bromide into methyl isobutyl ketone. Impregnation of the graphite furnace with sodium tungstate, and the presence of lithium metaborate and ascorbic acid in the reaction medium improve the sensitivity and precision. The limits of determination are 0.025-16 mg kg-1 indium in the sample. For 22 geological reference samples containing more than 0.1 mg kg-1 indium, relative standard deviations ranged from 3.0 to 8.5% (average 5.7%). Recoveries of indium added to various samples ranged from 96.7 to 105.6% (average 100.2%). ?? 1984.

  11. Determining the hydraulic properties of saturated, low-permeability geological materials in the laboratory: Advances in theory and practice

    USGS Publications Warehouse

    Zhang, M.; Takahashi, M.; Morin, R.H.; Endo, H.; Esaki, T.; ,

    2002-01-01

    The accurate hydraulic characterization of low-permeability subsurface environments has important practical significance. In order to examine this issue from the perspective of laboratory-based approaches, we review some recent advancements in the theoretical analyses of three different laboratory techniques specifically applied to low-permeability geologic materials: constant-head, constant flow-rate and transient-pulse permeability tests. Some potential strategies for effectively decreasing the time required to confidently estimate the permeability of these materials are presented. In addition, a new and versatile laboratory system is introduced that can implement any of these three test methods while simultaneously subjecting a specimen to high confining pressures and pore pressures, thereby simulating in situ conditions at great depths. The capabilities and advantages of this innovative system are demonstrated using experimental data derived from Shirahama sandstone and Inada granite, two rock types widely encountered in Japan.

  12. Building a Library Collection on Blindness and Physical Disabilities: Basic Materials and Resources. Reference Circular No. 90-3.

    ERIC Educational Resources Information Center

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

    The materials listed in this reference circular are recommended to libraries and organizations as basic resources for providing a current information service on visual impairments and physical disabilities. The selections, which are based on the holdings of the Reference Section of the National Library Service (NLS) for the Blind and Physically…

  13. 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…

  14. A GIS System for Inferring Subsurface Geology and Material Properties: Proof of Concept

    DTIC Science & Technology

    2006-09-01

    feature–constituent relationships defined in these tables. ER D C TR -06-6 16 Material type dolomitic/cherty limestone (humid) andesite ...Material type lava flows - darker tone indicates basalt; lighter tone, rhyolite or andesite waterlaid materials (flood plains) waterlaid...and gravel rather than alluvium; volcanic rock rather than basalt or andesite , and so on. We also determined that the terminology through- out the

  15. Well GeHP detector calibration for environmental measurements using reference materials

    NASA Astrophysics Data System (ADS)

    Tedjani, A.; Mavon, C.; Belafrites, A.; Degrelle, D.; Boumala, D.; Rius, D.; Groetz, J.-E.

    2016-12-01

    A well-type detector installed in the Modane underground Laboratory (LSM) can combine both low background and high detection efficiency and it is well suited for the analysis of small amounts of environmental samples. Reference materials such as IAEA-447 (moss-soil), IAEA-RG-Th1 and IAEA-RG-U1 were used for the detector calibration, owing to a chemical composition close to those of the environmental samples. Nevertheless, the matrix effects and the true coincidence summing effects must be corrected from the full energy peak efficiency (FEPE). The FEPE was performed for a wide range of energy by a semi-empirical method using Monte Carlo simulation (MCNP6), intended for environmental measurements such as lake sediments dating. In the well geometry, the true coincidence summing effects could be very important and correction factors have been computed in three different ways.

  16. Preparation and certification of arsenobetaine reference material NMIJ CRM 7901-a.

    PubMed

    Narukawa, Tomohiro; Chiba, Koichi; Kuroiwa, Takayoshi; Yarita, Takashi; Takatsu, Akiko

    2007-09-01

    An arsenobetaine [(CH(3))(3)As(+)CH(2)COO(-)] solution reference material, NMIJ CRM 7901-a, intended for use in the speciation of arsenic compounds, was developed and certified by the National Metrology Institute of Japan (NMIJ), part of the National Institute of Advanced Industrial Science and Technology (AIST). The high-purity arsenobetaine powder was synthesized from trimethylarsine [(CH(3))(3)As], and it was dissolved in water in order to prepare 20 mg kg(-1) of arsenobetaine standard solution. The solution was bottled in 500 bottles (each containing 10 ml). Certification of the CRM for arsenobetaine was conducted by NMIJ. The concentration of As was determined by four independent analytical techniques (ICP-MS, ICP-OES, GFAAS and LC-ICP-MS), and each result was converted to the arsenobetaine concentration by applying an appropriate factor. The arsenobetaine concentration in the CRM was thus certified.

  17. Preparation of waterproof OSL dosimeters from hygroscopic materials with a special reference to NaCl:Cu

    NASA Astrophysics Data System (ADS)

    More, Y. K.; Wankhede, S. P.; Patil, R. R.; Kulkarni, M. S.; Kumar, Munish; Moharil, S. V.

    2016-05-01

    Optically stimulated luminescence (OSL) originally developed for geological/archaeological dating, has been found very useful for diverse applications in the field of radiation dosimetry. There is still a scarcity of OSL materials with demonstrated properties suited to dosimetry applications. Progress on the development of OSL materials with engineered properties has been slow and most research has focused on the OSL characterization of existing materials. One of the reasons for availability of only a handful of OSL dosimetry materials with adequate properties is that they have to satisfy certain stringent conditions necessary for such applications. Especially, hygroscopic materials are considered totally unsuitable. The efforts were made in our laboratory to overcome this problem. It is shown here that "water-proof" dosimeters can be prepared from even hygroscopic materials such as NaCl.

  18. Estimation of uncertainty of a reference material for proficiency testing for the determination of total mercury in fish in nature

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

    We provide an uncertainty estimates for homogeneity and stability studies of reference material used in proficiency test for determination of total mercury in fish fresh muscle tissue. Stability was estimated by linear regression and homogeneity by ANOVA. The results indicate that the reference material is both homogeneous and chemically stable over the short term. Total mercury concentration of the muscle tissue, with expanded uncertainty, was 0.294 ± 0.089 μg g-1.

  19. Stability of ethyl glucuronide in hair reference materials after accelerated aging.

    PubMed

    Ammann, D; Becker, R; Nehls, I

    2015-12-01

    Two different hair reference materials, one produced from authentic hair displaying an ethyl glucuronide (EtG) content of about 25 pg/mg and one obtained by fortification of blank hair to an EtG level of 85 pg/mg were submitted to accelerated aging between 4 °C and 60 °C for periods between one and 24 months. Subsequently, the EtG content was determined in the aged samples and untreated reference samples stored at -22 °C under repeatability conditions following the so-called isochronous approach. The EtG content remained stable even at 40 °C for 24 months and at 60 °C over six months. This is in contrast to many organic analytes contained in trace concentrations in diverse matrices. A slight but significant increase of the recovered EtG in case of authentic hair samples having been exposed for 24 months between 4 °C and 60 °C may be due to a temperature-driven process that allows increased recoveries of the physiologically embedded EtG.

  20. 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

  1. Determination of palladium, platinum and rhodium in geologic materials by fire assay and emission spectrography

    USGS Publications Warehouse

    Hapfty, J.; Riley, L.B.

    1968-01-01

    A method is described for the determination of palladium down to 4ppb (parts per billion, 109), platinum down to 10 ppb and rhodium down to 5 ppb in 15 g of sample. Fire-assay techniques are used to preconcentrate the platinum metals into a gold bead, then the bead is dissolved in aqua regia and diluted to volume with 1M hydrochloric acid. The solution is analysed by optical emission spectrography of the residue from 200 ??l of it evaporated on a pair of flat-top graphite electrodes. This method requires much less sample handling than most published methods for these elements. Data are presented for G-1, W-1, and six new standard rocks of the U.S. Geological Survey. The values for palladium in W-1 are in reasonable agreement with previously published data. ?? 1968.

  2. First certified reference materials for molecular fingerprinting of two approved probiotic Bacillus strains.

    PubMed

    De Baets, L; Van Iwaarden, P; Meeus, N; Schimmel, H; Philipp, W; Emons, H

    2009-01-31

    At present probiotic bacteria are widely used in human and animal nutrition because they beneficially influence the balance of the intestinal flora of the host. Positive effects related to probiotics are various and include enhancement of digestion, strengthening of the immune system and stimulation of vitamin production. Moreover, implementation of probiotics is intended to reduce the use of antibiotics and improve animal growth and feed conversion. To protect human and animal health and to improve consumer confidence, a strict legislation on the use of probiotics exists within the European Union (EU). Official controls by national authorities are performed to ensure verification of compliance with feed and food law. Apart from the risk of using unauthorized strains, mislabelling is a known problem, partly because of the use of phenotyping or genotyping methods with a lack of discriminative power. In addition to official controls, private controls by food and feed producing companies are important in the frame of protection of patented strains and industrial property rights. To support these applications, IRMM has developed certified reference materials (CRMs) consisting of genomic DNA inserts of B. subtilis DSM 5749 and B. licheniformis DSM 5750, two strains that received EU approval. In this study we investigated the use of these CRMs, IRMM-311 and IRMM-312, for the detection and unambiguous discrimination of Bacillus strains by pulsed-field gel electrophoresis (PFGE). Identical fingerprints were obtained for the CRMs and control strains isolated from the feed additive Bioplus 2B. On the other hand a distinction could be made from other not approved B. licheniformis and B. subtilis strains. The reference materials discussed in this study are the first CRMs based on a whole bacterial genome and suitable for PFGE. They offer perspectives for applications in other domains such as analysis of foodborne pathogens in outbreaks or routine analysis.

  3. Characterization of 137 Genomic DNA Reference Materials for 28 Pharmacogenetic Genes

    PubMed Central

    Pratt, Victoria M.; Everts, Robin E.; Aggarwal, Praful; Beyer, Brittany N.; Broeckel, Ulrich; Epstein-Baak, Ruth; Hujsak, Paul; Kornreich, Ruth; Liao, Jun; Lorier, Rachel; Scott, Stuart A.; Smith, Chingying Huang; Toji, Lorraine H.; Turner, Amy; Kalman, Lisa V.

    2017-01-01

    Pharmacogenetic testing is increasingly available from clinical laboratories. However, only a limited number of quality control and other reference materials are currently available to support clinical testing. To address this need, the Centers for Disease Control and Prevention–based Genetic Testing Reference Material Coordination Program, in collaboration with members of the pharmacogenetic testing community and the Coriell Cell Repositories, has characterized 137 genomic DNA samples for 28 genes commonly genotyped by pharmacogenetic testing assays (CYP1A1, CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4, CYP3A5, CYP4F2, DPYD, GSTM1, GSTP1, GSTT1, NAT1, NAT2, SLC15A2, SLC22A2, SLCO1B1, SLCO2B1, TPMT, UGT1A1, UGT2B7, UGT2B15, UGT2B17, and VKORC1). One hundred thirty-seven Coriell cell lines were selected based on ethnic diversity and partial genotype characterization from earlier testing. DNA samples were coded and distributed to volunteer testing laboratories for targeted genotyping using a number of commercially available and laboratory developed tests. Through consensus verification, we confirmed the presence of at least 108 variant pharmacogenetic alleles. These samples are also being characterized by other pharmacogenetic assays, including next-generation sequencing, which will be reported separately. Genotyping results were consistent among laboratories, with most differences in allele assignments attributed to assay design and variability in reported allele nomenclature, particularly for CYP2D6, UGT1A1, and VKORC1. These publicly available samples will help ensure the accuracy of pharmacogenetic testing. PMID:26621101

  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. 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.

  6. An alternative method for the certification of the sulfur mass fraction in coal Standard Reference Materials.

    PubMed

    Winchester, M R; Kelly, W R; Mann, J L; Guthrie, W F; MacDonald, B S; Turk, G C

    2001-06-01

    The S mass fractions of coal SRMs 2682b, 2684b, and 2685b are certified by direct comparison with coal SRMs 2682a, 2684a, and 2685a, respectively, using high-temperature combustion analysis with infrared (IR) absorption detection. The S mass fractions of the "a" materials used for calibration were previously determined by means of isotope-dilution thermal-ionization mass spectrometry (ID-TIMS). Therefore, the comparisons performed with the combustion-IR absorption method establish direct traceability links to accurate and precise ID-TIMS measurements. The expanded uncertainties associated with the certified S mass fractions are of approximately the same magnitude as would be expected for the ID-TIMS methodology. An important aspect of these certifications is that each "b" material is essentially identical with the corresponding "a" material, because both were produced from the same bulk, homogenized coal. As a test of the efficacy of the new certification approach when calibrant and unknown are not identical, the S mass fraction of coal SRM 2683b has been determined by direct comparison to coal SRM 2683a. These two coals, which have both previously been analyzed with ID-TIMS, are different in terms of S content and other properties. Whereas the S mass fraction for SRM 2683b determined with the new methodology agrees statistically with the ID-TIMS value, there is reason for caution in such cases. In addition to the usefulness of the alternative approach for certification activities within NIST, this approach might also be an excellent way of establishing NIST traceability during the value assignment process for reference materials not issued by NIST. Further research is needed, however, to understand better the scope of applicability.

  7. Characterizing weathering intensity and trends of geological materials in the Gilgel Gibe catchment, southwestern Ethiopia

    NASA Astrophysics Data System (ADS)

    Regassa, Alemayehu; Van Daele, K.; De Paepe, P.; Dumon, M.; Deckers, J.; Asrat, Asfawossen; Van Ranst, E.

    2014-11-01

    Detailed geological and geochemical characterization is crucial to support soil studies in such geologically and topographically complex systems as the Gilgel Gibe catchment in southwestern Ethiopia. Field studies, as well as mineralogical, petrological and geochemical analyses on selected rock samples and their weathering products revealed that the catchment is dominantly underlain by rhyolites and trachytes, which occur as both lava flows and pyroclastic associations. Most of the lavas have a trachytic texture, while few others are massive or show spherulitic or perlitic texture. The rocks have a SiO2-content ranging from about 62 to 73 wt% (intermediate to felsic composition, on an anhydrous base) and a relatively high Na2O + K2O content ranging from about 9 to 12 wt% (anhydrous base). The dominant phenocrysts present in the rocks are plagioclase, sanidine and Fe-Ti oxide minerals. Alkali-rich amphiboles and quartz occur in most of them, while hornblende, titanite and clinopyroxene are rare. The amount of phenocrysts varies from less than 1 vol.% to about 30 vol.%. The pyroclastic associations are discontinuously scattered within the study area. They all have a glassy matrix (vitrophyric texture) and are composed of a mixture of lithics, crystals and glass. In comparison with the lava samples, the pyroclastic samples exhibit a more variable chemistry. In contrast, the X-ray diffractograms of the pyroclastic deposits and the lavas show little difference. The Chemical Index of Alteration values for the studied samples vary from 53 to 99 indicating moderate to high intensity of weathering. Samples from lava flows have shown less degree of weathering than samples of the pyroclastic associations.

  8. Geologic Mapping and Paired Geochemical-Paleomagnetic Sampling of Reference Sections in the Grande Ronde Basalt: An Example from the Bingen Section, Columbia River Gorge, Washington

    NASA Astrophysics Data System (ADS)

    Sawlan, M.; Hagstrum, J. T.; Wells, R. E.

    2011-12-01

    We have completed comprehensive geochemical (GC) and paleomagnetic (PM) sampling of individual lava flows from eight reference stratigraphic sections in the Grande Ronde Basalt (GRB), Columbia River Basalt Group [Hagstrum et al., 2009, GSA Ann. Mtg, Portland (abst); Hagstrum et al., 2010, AGU Fall Mtg, San Francisco (abst)]. These sections, distributed across the Columbia Plateau and eastern Columbia River Gorge, contain as many as 30 flows, are up to 670 m thick, span upper magneto-stratigraphic zones R2 and N2, and, in some locations, also contain one or more N1 flows. In concert with GC and PM sampling, we have carried out detailed geologic mapping of these sections, typically at a scale of 1:3,000 to 1:5,000, using GPS, digital imagery from the National Aerial Imagery Program (NAIP), and compilation in GIS. GRB member and informal unit names of Reidel et al. [1989, GSA Sp. Paper 239] generally have been adopted, although two new units are identified and named within the N2 zone. Notably, a distinctive PM direction for intercalated lavas of several lower N2 units indicates coeval eruption of compositionally distinct units; this result contrasts with the scenario of serial stratigraphic succession of GRB units proposed by Reidel et al. [1989]. Our objectives in the mapping include: Confirming the integrity of the stratigraphic sequences by documenting flow contacts and intraflow horizons (changes in joint patterns or vesicularity); assessing fault displacements; and, establishing precisely located samples in geologic context such that selected sites can be unambiguously reoccupied. A geologic map and GC-PM data for the Bingen section, along the north side of the Columbia River, are presented as an example of our GRB reference section mapping and sampling. One of our thicker sections (670 m) along which 30 flows are mapped, the Bingen section spans 7 km along WA State Hwy 14, from near the Hood River Bridge ESE to Locke Lake. This section cuts obliquely through a

  9. Introduction to selected references on fossil fuels of the central and southern Appalachian basin: Chapter H.1 in Coal and petroleum resources in the Appalachian basin: distribution, geologic framework, and geochemical character

    USGS Publications Warehouse

    Ruppert, Leslie F.; Lentz, Erika E.; Tewalt, Susan J.; Román Colón, Yomayra A.; Ruppert, Leslie F.; Ryder, Robert T.

    2014-01-01

    The Appalachian basin contains abundant coal and petroleum resources that have been studied and extracted for at least 150 years. In this volume, U.S. Geological Survey (USGS) scientists describe the geologic framework and geochemical character of the fossil-fuel resources of the central and southern Appalachian basin. Separate subchapters (some previously published) contain geologic cross sections; seismic profiles; burial history models; assessments of Carboniferous coalbed methane and Devonian shale gas; distribution information for oil, gas, and coal fields; data on the geochemistry of natural gas and oil; and the fossil-fuel production history of the basin. Although each chapter and subchapter includes references cited, many historical or other important references on Appalachian basin and global fossil-fuel science were omitted because they were not directly applicable to the chapters.

  10. A geological study of clayey laterite and clayey hydromorphic material of the region of Yaoundé (Cameroon): a prerequisite for local material promotion

    NASA Astrophysics Data System (ADS)

    Ngon Ngon, G. F.; Yongue–Fouateu, R.; Bitom, D. L.; Bilong, P.

    2009-09-01

    A geological survey carried out in the Yaoundé (Cameroon) region has revealed the presence of homogeneous clayey laterite in the upper part of a laterite cover on interfluves, thickest on hills (780-800 m altitude) where ferricrete is absent, and clayey heterogeneous hydromorphic material in valleys. We present in this paper the physical, mineralogical and geochemical properties of these occurrences and discuss their potential as raw material for pottery, manufacture of bricks and tiles. These clayey raw materials are mostly made up of fine particles (ranging from 55 to 60% clay + silt in the clayey laterite, more than 70% clay + silt in the clayey hydromorphic material). Their chemical composition is characterized by silica (<60% SiO 2), alumina (<35% Al 2O 3) and iron (ranging from 3 to 14% Fe 2O 3). Their main clay minerals are disorganized and poorly crystallized kaolinites. The average limits of liquidity (44.56% versus 91.58%) and limits of plasticity (22.4 versus 45.93) revealed that clayey hydromorphic material has the greatest plasticity. The studied raw materials are suitable for making pottery as well as the manufacture of bricks and tiles. However, the high iron content in the clayey laterite (between 11 and 12% Fe 2O 3) prevents their efficient use in the manufacture of ceramics.

  11. 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.

  12. Two new standard reference materials for the determination of drugs of abuse in human hair.

    PubMed

    Welch, Michael J; Sniegoski, Lorna T; Tai, Susan

    2003-08-01

    Two new standard reference materials (SRM) for drugs of abuse in human hair have been developed. SRM 2379 consists of hair spiked with cocaine, benzoylecgonine, cocaethylene, phencyclidine, amphetamine, and methamphetamine. SRM 2380 consists of hair spiked with codeine, morphine, monoacetylmorphine, and tetrahydrocannabinol (THC). The SRMs were prepared by soaking the hair in a solution of the target analytes in water-dimethylsulfoxide. The concentration of each analyte was determined using two methods, one based upon gas chromatography/mass spectrometry (GC/MS) and one based upon liquid chromatography/mass spectrometry (LC/MS). Both methods used 0.1 M HCl for extraction of all the analytes from the hair, except for THC, which was extracted with 1 M NaOH. For isolation of the analytes from the extracts, the GC/MS-based methods used different clean-up procedures from those used for the LC/MS-based methods. The results from the two methods were in good agreement with mean differences for the analytes ranging from 4% to 16%. These materials will enable laboratories performing analyses of hair for drugs of abuse to test the accuracy of their methods.

  13. 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

    2008-07-04

    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.

  14. Influence of tile-drainage on groundwater flow and nitrate transport in heterogeneous geological materials

    NASA Astrophysics Data System (ADS)

    De Schepper, G.; Therrien, R.; Refsgaard, J.

    2012-12-01

    Subsurface drainage is a common agricultural practice in poorly drained production fields to guarantee the productivity of crops and to reduce flooding risks. The impact of shallow tile-drainage networks on groundwater flow patterns and associated nitrate transport from the surface needs to be quantified for adequate agricultural management. A challenge is to represent tile-drain networks in numerical models, at the field scale, while accounting for the influence of subsurface heterogeneities on flow and transport. A numerical model of a tile-drainage system has been developed with the fully integrated HydroGeoSphere model for the Lillebaek agricultural catchment, Denmark. The Lillebaek catchment is an experimental study area where hydraulic heads, stream and drain discharges, as well as groundwater and surface water nitrate concentrations are regularly measured. This catchment includes various tile-drainage networks that are monitored on a daily basis; the one we have been focusing on is about 5 ha within a 34 ha model domain. The Lillebaek catchment subsurface is made of about 30 m thick Quaternary deposits which consist of a local sandy aquifer with upper and lower clayey till units, confining the aquifer in the upper part. The main modelling objective is to assess the influence of tile drains on the water flow pattern within the confining clayey till unit with and on the nitrate reduction zone depth, also known as the redox-interface, while accounting for local geological heterogeneities. Using the national-scale geological model for Denmark combined with available local data, a hydrogeological model at field scale has been generated. A proper representation of the tile-drains geometry is essential to calibrate and validate the water flow model associated with nitrate transport. HydroGeoSphere can represent drains directly into a model as one-dimensional features, which however requires a very fine mesh discretization that limits the size of the simulation

  15. Certification of drugs of abuse in a human serum standard reference material: SRM 1959.

    PubMed

    Tai, Susan S-C; Prendergast, Jocelyn L; Sniegoski, Lorna T; Welch, Michael J; Phinney, Karen W; Zhang, Nien Fan

    2010-05-01

    A new standard reference material (SRM) for drugs of abuse in human serum (SRM 1959) has been developed. This SRM is intended to be used as a control material for laboratories performing analysis of drugs of abuse in blood to evaluate the accuracy of their methods. SRM 1959 is a frozen human serum material fortified with seven compounds for which analyses are performed to determine evidence of illegal drug use: benzoylecgonine (BZE), methadone (METH), methamphetamine (MAMP), morphine (MOR), nordiazepam (NOR), phencyclidine (PCP), and 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-9-COOH). Two independent methods involving isotope dilution (ID)-gas chromatography/mass spectrometry (GC/MS) and ID-liquid chromatography/mass spectrometry (LC/MS) were used for the value assignment. For THC-9-COOH, an additional measurement using LC/tandem mass spectrometry (LC/MS/MS) was also included. All methods used isotopically labeled compounds as internal standards and solid-phase extractions to isolate the analytes from the serum. The GC/MS methods used different clean-up procedures from those used for the LC/MS-based methods. Repeatability with within-set coefficients of variation (CVs) ranged from 0.5% to 4.3% for the GC/MS methods and from 0.2% to 1.2% for the LC/MS-based methods. Intermediate precision with between-set CVs for all the methods ranged from 0.1% to 1.1%. Agreement between the GC/MS and LC/MS methods ranged from 0.8% to 8.8%. The results from the methods were combined to obtain the certified concentrations and their expanded uncertainties.

  16. [Report of the NEDO project "Research and development to promote the creation and utilization of an intellectual infrastructure: development of reference materials for laboratory medicine" "Development of pure substance-type certified reference materials"].

    PubMed

    Takatsu, Akiko

    2009-06-01

    There is an increasing demand to establish a metrological traceability system for in vitro diagnostics and medical devices. Pure substance-type reference materials are playing key roles in metrological traceability, because they form the basis for many traceability chains in chemistry. The National Metrology Institute of Japan (NMIJ), in the National Institute of Advanced Industrial Science and Technology (AIST), has been developing purity-certified reference materials (CRMs) in this field, such as cholesterol, creatinine, and urea. In the New Energy and Industrial Technology Development Organization (NEDO) project, entitled: "Research and Development to Promote the Creation and Utilization of an Intellectual Infrastructure: Development of Reference Materials for Laboratory Medicine", several pure substance-type CRMs were developed. For a pure protein solution CRM, amino acid analysis and nitrogen determination were chosen as the certification methods. The development and certification processes for the C-reactive protein (CRP) solution CRM were completed, with the recombinant human CRP solution as a candidate material. This CRP solution CRM is now available as NMIJ CRM. For cortisol CRM, a purified candidate material and highly pure primary reference material were prepared. Each impure compound in the materials was identified and quantified. The pure cortisol CRM will be available in 2009. These two CRMs provide a traceability link between routine clinical methods and the SI unit.

  17. Arsenic removal from groundwater of the Chaco-Pampean plain (Argentina) using natural geological materials as adsorbents.

    PubMed

    Bundschuh, Jochen; Bhattacharya, Prosun; Sracek, Ondra; Mellano, M Fernanda; Ramírez, Antonio E; Storniolo, Angel del R; Martín, Raúl A; Cortés, Julia; Litter, Marta I; Jean, Jiin-Shuh

    2011-01-01

    Use of natural geological materials for arsenic (As) removal is an emerging solution at a household level for poor people in remote rural settlements, especially when the materials are locally available and can be collected by the local population. Their low or zero cost makes these materials very attractive compared with synthetic or commercial materials. Sometimes, this may be the only option to provide safe water to very poor settlements. Their suitability for As removal from water is mainly due to adsorption, co-precipitation and ion exchange processes involving Fe- and Al-rich minerals and clay minerals present in the soils or sediments. In the present study, various clay-rich soils from the Santiago del Estero province (SDE, NW Argentina) and, for comparison, a laterite from the Misiones province have been tested as adsorbents for As in shallow naturally contaminated groundwaters of the Río Dulce alluvial aquifer in SDE. Batch adsorption experiments showed higher As(V) removal for the Misiones laterite sample (99 %) as compared with the soils from SDE (40-53 %), which can be related to lower contents of water-soluble and oxalate extractable Al and Fe in the last samples. These results suggest the application of the Misiones laterite soil as an alternative for As removal. However, high transportation costs from Misiones to SDE can be an economical restriction for the low-income population of SDE.

  18. Atomic-absorption spectrometric determination of cobalt, nickel, and copper in geological materials with matrix masking and chelation-extraction

    USGS Publications Warehouse

    Sanzolone, R.F.; Chao, T.T.; Crenshaw, G.L.

    1979-01-01

    An atomic-absorption spectrometric method is reported for the determination of cobalt, nickel, and copper in a variety of geological materials including iron- and manganese-rich, and calcareous samples. The sample is decomposed with HP-HNO3 and the residue is dissolved in hydrochloric acid. Ammonium fluoride is added to mask iron and 'aluminum. After adjustment to pH 6, cobalt, nickel, and copper are chelated with sodium diethyl-dithiocarbamate and extracted into methyl isobutyl ketone. The sample is set aside for 24 h before analysis to remove interferences from manganese. For a 0.200-g sample, the limits of determination are 5-1000 ppm for Co, Ni, and Cu. As much as 50% Fe, 25% Mn or Ca, 20% Al and 10% Na, K, or Mg in the sample either individually or in various combinations do not interfere. Results obtained on five U.S. Geological Survey rock standards are in general agreement with values reported in the literature. ?? 1979.

  19. Development of a new certified reference material of diosgenin using mass balance approach and Coulometric titration method.

    PubMed

    Gong, Ningbo; Zhang, Baoxi; Hu, Fan; Du, Hui; Du, Guanhua; Gao, Zhaolin; Lu, Yang

    2014-12-01

    Certified reference materials (CRMs) can be used as a valuable tool to validate the trueness of measurement methods and to establish metrological traceability of analytical results. Diosgenin has been selected as a candidate reference material. Characterization of the material relied on two different methods, mass balance method and Coulometric titration method (CT). The certified value of diosgenin CRM is 99.80% with an expanded uncertainty of 0.37% (k=2). The new CRM of diosgenin can be used to validate analytical methods, improve the accuracy of measurement data and control the quality of diosgenin in relevant pharmaceutical formulations.

  20. NIST bullet signature measurement system for RM (Reference Material) 8240 standard bullets.

    PubMed

    Ma, Li; Song, John; Whitenton, Eric; Zheng, Alan; Vorburger, Theodore; Zhou, Jack

    2004-07-01

    A bullet signature measurement system based on a stylus instrument was developed at the National Institute of Standards and Technology (NIST) for the signature measurements of NIST RM (Reference Material) 8240 standard bullets. The standard bullets are developed as a reference standard for bullet signature measurements and are aimed to support the recently established National Integrated Ballistics Information Network (NIBIN) by the Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI). The RM bullets are designed as both a virtual and a physical bullet signature standard. The virtual standard is a set of six digitized bullet signatures originally profiled from six master bullets fired at ATF and FBI using six different guns. By using the virtual signature standard to control the tool path on a numerically controlled diamond turning machine at NIST, 40 RM bullets were produced. In this paper, a comparison parameter and an algorithm using auto-and cross-correlation functions are described for qualifying the bullet signature differences between the RM bullets and the virtual bullet signature standard. When two compared signatures are exactly the same (point by point), their cross-correlation function (CCF) value will be equal to 100%. The measurement system setup, measurement program, and initial measurement results are discussed. Initial measurement results for the 40 standard bullets, each measured at six land impressions, show that the CCF values for the 240 signature measurements are higher than 95%, with most of them even higher than 99%. These results demonstrate the high reproducibility for both the manufacturing process and the measurement system for the NIST RM 8240 standard bullets.

  1. Development of palm-based reference materials for the quantification of fatty acids composition.

    PubMed

    Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai; Kuntom, Ainie

    2008-01-01

    Characterisation of fatty acids composition of three palm-based reference materials was carried out through inter-laboratory proficiency tests. Twelve laboratories collaborated in these tests and the fatty acids compositions of palm oil, palm olein and palm stearin were determined by applying the MPOB Test Methods p3.4:2004 and p3.5:2004. Determination of consensus values and their uncertainties were based on the acceptable statistical agreement of results obtained from the collaborating laboratories. The consensus values and uncertainties (%) for each palm oil reference material produced are listed as follows : 0.20% (C12:0), 1.66+/-0.05% (C14:0), 43.39+/-0.39% (C16:0), 0.14+/-0.06% (C16:1), 3.90+/-0.11% (C18:0), 40.95+/-0.23% (C18:1), 9.68+/-0.21% (C18:2), 0.16+/-0.07% (C18:3) and 0.31+/-0.08% (C20:0) for fatty acids composition of palm oil; 0.23+/-0.04% (C12:0), 1.02+/-0.04% (C14:0), 39.66+/-0.19% (C16:0), 0.18+/-0.07% (C16:1), 3.81+/-0.04% (C18:0), 44.01+/-0.08% (C18:1), 10.73+/-0.08% (C18:2), 0.20+/-0.06% (C18:3) and 0.34+/-0.04% (C20:0) for fatty acids composition of palm olein; and 0.20% (C12:0), 1.14+/-0.05% (C14:0), 49.42+/-0.25% (C16:0), 0.16+/-0.08% (C16:1), 4.15+/-0.10% (C18:0), 36.14+/-0.77% (C18:1), 7.95+/-0.29% (C18:2), 0.11+/-0.07% (C18:3) and 0.30+/-0.08% (C20:0) for fatty acids composition of palm stearin.

  2. Accurate measurement of silver isotopic compositions in geological materials including low Pd/Ag meteorites

    NASA Astrophysics Data System (ADS)

    Woodland, S. J.; Rehkämper, M.; Halliday, A. N.; Lee, D.-C.; Hattendorf, B.; Günther, D.

    2005-04-01

    Very precise silver (Ag) isotopic compositions have been determined for a number of terrestrial rocks, and high and low Pd/Ag meteorites by utilizing multicollector inductively coupled plasma mass spectrometry (MC-ICPMS). The meteorites include primitive chondrites, the Group IAB iron meteorites Canyon Diablo and Toluca, and the Group IIIAB iron meteorite Grant. Silver isotopic measurements are primarily of interest because 107Ag was produced by decay of the short-lived radionuclide 107Pd during the formation of the solar system and hence the Pd-Ag chronometer has set constraints on the timing of early planetesimal formation. A 2σ precision of ±0.05‰ can be obtained for analyses of standard solutions when Ag isotopic ratios are normalized to Pd, to correct for instrumental mass discrimination, and to bracketing standards. Caution must be exercised when making Ag isotopic measurements because isotopic artifacts can be generated in the laboratory and during mass spectrometry. The external reproducibility for geological samples based on replicate analyses of rocks is ±0.2‰ (2σ). All chondrites analyzed have similar Ag isotopic compositions that do not differ significantly (>0.3‰) from the 'terrestrial' value of the NIST SRM 978a Ag isotope standard. Hence, they show no evidence of excess 107Ag derived from 107Pd decay or, of stable Ag isotope fractionation associated with volatile element depletion within the accretion disk or from parent body metamorphism. The Group IAB iron meteorite samples analyzed show evidence of complex behavior and disturbance of Ag isotope systematics. Therefore, care must be taken when using this group of iron meteorites to obtain chronological information based on the Pd-Ag decay scheme.

  3. Estimating the water content of geologic materials using near-infrared reflectance spectroscopy: Applications to laboratory and spacecraft data

    NASA Astrophysics Data System (ADS)

    Milliken, Ralph Edward

    Visible-near infrared reflectance spectroscopy has been used to relate the absorption strength of the 3 micrometer hydration feature to absolute water content (weight percent) of hydrated geologic materials. Complicating factors of albedo, particle size, and composition were examined individually. Laboratory results combining spectral measurements of materials under ambient, low relative humidity, and heated conditions with measurements of water content provide a method to link changes in band strength to changes in water content for materials under varying hydration states. Primary results indicate that reflectance spectra should be converted to single scattering albedo in order to accurately estimate water content for a wide variety of clay minerals, sulfates, zeolites, and hydrated volcanic materials. These methods are applicable to both laboratory and remotely sensed reflectance spectra. Application of our hydration model to high-resolution Mars Express OMEGA spectra of the martian surface reveal that bright and dark regions have similar water contents in the equatorial latitudes (2--4 wt. %), hydration increases with latitude poleward of ˜60°N (up to 8--15 wt. %), and local outcrops of sulfate and phyllosilicate material exhibit water contents of 5--8 wt. %. Furthermore, high latitude surfaces exhibit seasonal changes in water content on the order of 2--3 wt. %, likely the result of water vapor exchange between the regolith and atmosphere. The methods and model presented here provide a robust, non-destructive technique for estimating the water content of particulate samples spanning a wide albedo range (0.07--0.9), particle size (<250 mum), and composition (well-ordered to poorly crystalline). Applying these models to laboratory samples and spacecraft data will provide insight into the hydration state of terrestrial and planetary materials and the location, amount, and role of water in the solar system under current and past conditions.

  4. Potential uses of stable isotope ratios of Sr, Nd, and Pb in geological materials for environmental studies.

    PubMed

    Nakano, Takanori

    2016-01-01

    The ratios of stable isotopes of certain elements in rocks and minerals have strong regional characteristics that are reflected in atmospheric components, in water, and in the living organisms that form Earth's surface environment as well as in agricultural and fishery products. Geologically derived stable isotope ratios can be used as a tracer for the source of many kinds of substances, with current geochemical techniques allowing the precise determination of numerous stable isotope ratios in both natural and manmade objects. This review presents examples of the use of stable isotopes as tracers within diverse dynamic ecosystems, focusing on Sr isotopes but also including examples of Nd and Pb isotopic analysis, and reviewing the potential of this technique for a wide range of environmental research, including determining the geographic origin of food and archeological materials.

  5. Potential uses of stable isotope ratios of Sr, Nd, and Pb in geological materials for environmental studies

    PubMed Central

    NAKANO, Takanori

    2016-01-01

    The ratios of stable isotopes of certain elements in rocks and minerals have strong regional characteristics that are reflected in atmospheric components, in water, and in the living organisms that form Earth’s surface environment as well as in agricultural and fishery products. Geologically derived stable isotope ratios can be used as a tracer for the source of many kinds of substances, with current geochemical techniques allowing the precise determination of numerous stable isotope ratios in both natural and manmade objects. This review presents examples of the use of stable isotopes as tracers within diverse dynamic ecosystems, focusing on Sr isotopes but also including examples of Nd and Pb isotopic analysis, and reviewing the potential of this technique for a wide range of environmental research, including determining the geographic origin of food and archeological materials. PMID:27302069

  6. Polybrominated diphenyl ether congeners and toxaphene in selected marine standard reference materials.

    PubMed

    Kucklick, John R; Tuerk, Karen J S; Vander Pol, Stacy S; Schantz, Michele M; Wise, Stephen A

    2004-03-01

    Polybrominated diphenyl ether (PBDE) congeners and components of the complex mixture toxaphene are stable in the environment and readily bioaccumulated into wildlife and human tissues. PBDEs are presently used in large quantities worldwide as flame retardants in textiles, furniture, computer equipment, and cables. Toxaphene is a complex mixture of chlorinated bornanes and bornenes that was the most heavily used pesticide in the United States until it was banned in 1982; however, some countries continue to use toxaphene. The National Institute of Standards and Technology has quantified PBDE congeners and toxaphene in several available Standard Reference Materials (SRMs) using methods of gas chromatography with electron impact mass spectrometry (GC-EI-MS) and GC negative chemical ionization (NCI) MS, respectively. SRM 1588a Organics in Cod Liver Oil and SRM 1945 Organics in Whale Blubber were examined for PBDE congeners 47, 99, 100, 153, and 154, total toxaphene, and toxaphene congeners 26, 50, and 62. SRM 1946 Lake Superior Fish Tissue was also examined for total toxaphene and toxaphene congeners. The sum of the PBDE congeners (mean, (1 SD) wet basis) for SRM 1945 was 150 ng g(-1) (7 ng g(-1)). The concentration of PBDE 47 in SRM 1588a was 82.7 ng g(-1) (2.8 ng g(-1)). Other PBDEs were detected in SRM 1588a but were not quantified due their low levels. The total toxaphene (wet mass basis) was 1,210 ng g(-1) (127 ng g(-1)), 1,960 ng g(-1) (133 ng g(-1)), and 3,980 ng g(-1) (248 ng g(-1)) in SRMs 1945, 1946, and 1588a, respectively. The values for PBDEs and toxaphene determined in the SRMs, while not certified, indicate that the SRMs will be suitable control materials for PBDE and toxaphene analyses.

  7. Effects of native organic material and water on sorption properties of reference diesel soot.

    PubMed

    Endo, Satoshi; Grathwohl, Peter; Haderlein, Stefan B; Schmidt, Torsten C

    2009-05-01

    Soot has been considered as a potentially important sorbent for organic contaminants in soils, sediments, and aerosols. This paper demonstrates that native (authigenic) extractable organic material (EOM) and surface-covering water on soot may have a substantial influence on sorption properties of the soot. Sorption isotherms were determined for apolar and weakly polar sorbates (n-octane, cyclooctane, n-propylbenzene, naphthalene) from an aqueous solution to a standard reference material of diesel soot (SRM 2975) in the original state and after extraction with methanol. For all sorbates tested, removal of EOM from soot by methanol caused the sorption isotherms to be more nonlinear (decrease of Freundlich exponents by 0.19-0.25) compared to the untreated soot. The changes in the isotherms depend on both sorbate structure and sorbate concentration and can be accounted for by two opposing roles that EOM could have on the sorption properties of soot (i) enhancing the overall sorption by absorbing the sorbate into the EOM phase, and (ii) attenuating the sorbate adsorption to the soot carbon surface through sorption competition or site blockage. The n-alkane-to-cycloalkane sorption coefficient ratios (Kn/Kc) indicated that the removal of EOM altered the sorption mode for alkanes from absorption to adsorption. A comparison of the sorption isotherms measured in aqueous suspensions with the soot-air sorption coefficients reported for SRM 2975 in the literature showed that sorption to "soot in water" is significantly weaker than sorption to "soot in air", indicating that complete surface coverage with water suppresses the sorption by soot.

  8. 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.

  9. Principles of Geological Mapping of Marine Sediments (with Special Reference to the African Continental Margin). Unesco Reports in Marine Science No. 37.

    ERIC Educational Resources Information Center

    Lisitzin, Alexandre P.

    Designed to serve as a complement to the Unesco Technical Papers in Marine Science, this report concentrates on theoretical and practical problems of geological mapping of the sea floor. An introduction is given to geological mapping procedures at continental margins as well as some practical recommendations taking as an example the African region…

  10. Reference Materials and Services for a Small Hospital Library. 5th Revised Edition.

    ERIC Educational Resources Information Center

    Kesti, Julie, Comp.; Graham, Elaine, Comp.

    This manual suggests and describes recommended reference services and sources for a small hospital library. Focusing on reference services, the first section includes information on ready-reference services; bibliographic search services, including taking and processing a request for a bibliography, National Library of Medicine literature…

  11. 40 CFR 1060.810 - What materials does this part reference?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (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 C700... material. Table 2 to this section lists material from the Society of Automotive Engineers that we...

  12. Determination of thorium in geological materials by x-ray fluorescence spectrometry after anion exchange extraction

    SciTech Connect

    Roelandts, I.

    1983-08-01

    The exchange capacity of the resin was determined to be 1 m equiv of Th/g dry resin. Synthetic calibration standards of thorium were prepared over a large concentration range, for use as an independent method of calibration. The advantages and disadvantages of direct x-ray fluorescence analysis are discussed. The lower limit of detection has been calculated according to Currie's convention and was found to be equal to 13 ..mu..g of Th/250 mg of resin, sufficient for the range of concentrations found in Th bearing minerals and ores. Results using Canadian syenite rocks and a suite of South African reference minerals show that the proposed method appears to be relatively precise and accurate for exploration geochemistry. 1 figure, 2 tables.

  13. Development of the NBS /sup 10/Be//sup 9/Be isotopic standard reference material

    SciTech Connect

    Inn, K.G.W.; Raman, S.; Coursey, B.M.; Fassett, J.D.; Walker, R.L.

    1987-04-01

    The National Bureau of Standards (NBS), in conjunction with the Oak Ridge National Laboratory (ORNL) and the Accelerator Mass Spectrometry (AMS) community, is in the process of developing a /sup 10/Be//sup 9/Be isotopic solution Standard Reference Material (SRM). The starting /sup 10/Be//sup 9/Be solution was provided by the ORNL after Secondary Ionization Mass Spectrometric characterization for isotopic concentration. The radioactivity purity of the ORNL Master solution was confirmed by gamma-ray spectrometry, then diluted at NBS with solutions made from zone-refined single-crystal beryllium metal and sub-boiling double-distilled hydrochloric acid. Four serial dilutions were necessary to achieve a final /sup 10/Be//sup 9/Be isotopic composition of approximately 3 x 10/sup -11/ (g/g). The accuracy of the dilutions was confirmed by liquid scintillation and AMS measurements. The isotopic composition of the ORNL Master solution was also confirmed at NBS by Resonant Ionization Mass Spectrometry. The isotopic composition of the final solution is being affirmed at the present time through international laboratory AMS measurements.

  14. Determination of total chromium in Marine Sediment Reference Material BCSS-1.

    PubMed

    Liu>, J.; Sturgeon, R. E.; Boyko, V. J.; Willie, S. N.

    1996-12-01

    The determination of Cr in National Research Council of Canada Marine Sediment Reference Material BCSS-1 is addressed. Mixed acid digestions utilizing HF, HClO(4) and HNO(3) were investigated. Single microwave assisted digestions in closed vessels at medium pressures (8 bar) were inappropriate (80% recovery). Double digestion at moderate pressure and digestions at high pressure (70 bar) or lengthy open-beaker hot plate dissolutions resulted in 93+/-5% recovery of certified Cr content. Flame atomic absorption and inductively coupled plasma atomic emission spectrometry were used for quantitation. In all cases, the method of standard additions was necessary to eliminate the approximately 10% enhancement in re- sponce relative to unmatched standards. Compared to a certified content of 123+/-7 microg/g (mean and standard deviation), values of 116+/-6 were obtained using an open beaker digestion; 114+/-5 using a double microwave digestion at 8 bar; 113+/-2 for microwave digestion at high pressure and 111+/-4 at high pressure (81 bar) with triple microwave digestion in a Parr bomb. No acid dissolution procedure is adequate for Cr in this sample although recovery of total Cr is complete from National Institute of Standards and Technology Buffalo River Sediment (SRM 2704).

  15. Certified reference material of bioethanol for metrological traceability in electrochemical parameters analyses.

    PubMed

    Serta Fraga, Isabel Cristina; Ribeiro, Carla Matos; Sobral, Sidney Pereira; Dias, Júlio Cesar; Gonçalves, Mary Ane; Borges, Paulo Paschoal; Gonzaga, Fabiano Barbieri

    2012-09-15

    Bioethanol has become an important biofuel because it is a source of renewable energy and can help to decrease global warming. However, the quality of bioethanol needs to be guaranteed so that it can be trusted and accepted in international trade. The Brazilian Metrology Institute (Inmetro) has been developing a certified reference material (CRM) for bioethanol to ensure quality control for measurement in the bioethanol matrix. Inmetro has certified 11 quality parameters. Using these, the CRM of bioethanol will contribute to guaranteeing metrological traceability and reliable measurement results. These factors can be used to compare different bioethanols produced to comply with legislation in different countries in order to avoid technical barriers and thus increase the international trade in Brazilian bioethanol. The aim of this paper is to present the results of certification studies using three important electrochemical quality parameters in the CRM of bioethanol-total acid number, pHe and electrolytic conductivity-which are crucial in protecting the metallic parts of a vehicle from corrosion. The certified results obtained for total acid number, pHe and electrolytic conductivity parameters were (16.2±1.7)mg L(-1), 6.07±0.30, and (1.03±0.11)μS cm(-1), respectively. The uncertainties for all parameters were the expanded uncertainty obtained by multiplying the combined standard uncertainty by a coverage factor of k=2, which represents an approximately 95% confidence level.

  16. Long-term stability of hydrocarbons in NIST gas standard reference material (SRM) 1800.

    PubMed

    Rhoderick, George C

    2005-09-01

    A gas standard reference material (SRM) containing fifteen hydrocarbons in nitrogen at a nominal 5 nmol mol(-1) was issued in 1993. The certification period for SRM 1800 was assigned as 2 years, because of limited stability data. Over a period of 10 years reanalysis of the lot standard (a sample chosen from the SRM lot to which all other lot samples are compared), SRM samples remaining in stock for sale, and SRMs returned to the National Institute of Standards and Technology (NIST) for recertification, were compared with primary standards to assess the stability of the hydrocarbons. New primary standards were periodically introduced into the original primary standard suite to assess the stability and consistency of the primary standards. Over this ten-year period 11 SRM 1800 samples were reanalyzed, resulting in 210 amount-of-substance fraction (concentration) determinations performed for quality-assurance purposes. Of these measurements 209 (99.5%) agreed within the original 95% confidence interval of the +/-4% expanded uncertainty, demonstrating the stability of the standards. There was also agreement to within +/-2% of the original concentration for 204 (97%) of the measurements. This is well within the original +/-4% expanded uncertainty assigned to the hydrocarbon concentrations at the approximate 95% confidence interval demonstrating stability. These results will enable the expiry date to be increased for future restock issues of SRM 1800.

  17. 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.

  18. Proposal for C-Hordein as Reference Material in Gluten Quantification.

    PubMed

    Huang, Xin; Kanerva, Päivi; Salovaara, Hannu; Stoddard, Frederick L; Sontag-Strohm, Tuula

    2017-03-15

    The concentration of residual barley prolamin (hordein) in gluten-free products is overestimated by the R5 ELISA method when calibrated against the wheat gliadin standard. The reason for this may be that the composition of the gliadin standard is different from the composition of hordeins. This study showed that the recognition of whole hordein by R5 antibody mainly came from C-hordein, which is more reactive than the other hordeins. The proportion of C-hordein in total hordein ranged from 16 to 33% of common Finnish barley cultivars used in this study and was always higher than that of ω-gliadin, the homologous protein class in the gliadin standard, which may account for the overestimation. Thus, a hordein standard is needed for barley prolamin quantification instead of the gliadin standard. When gluten-free oat flour was spiked with barley flour, the prolamin concentration was overestimated 1.8-2.5 times with the gliadin standard, whereas estimates in the correct range were obtained when the standard was 40% C-hordein mixed with an inert protein. A preparative-scale method was developed to isolate and purify C-hordein, and C-hordein is proposed as a reference material to calibrate barley prolamin quantification in R5-based assays.

  19. 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.

  20. Development of hemoglobin A1c certified reference material by liquid chromatography isotope dilution mass spectrometry.

    PubMed

    Bi, Jiaming; Wu, Liqing; Yang, Bin; Yang, Yi; Wang, Jing

    2012-04-01

    We report the development of a National Institute of Metrology (NIM) hemoglobin A(1c) (HbA(1c)) certified reference material (CRM). Each CRM unit contains about 10 μL of hemoglobin. Both hemoglobin and glycated hemoglobin were quantitatively determined by high-performance liquid chromatography (HPLC)-isotope dilution mass spectrometry (IDMS) with synthesized VHLTPE and glycated VHLTPE as standards. The mass fraction of synthesized VHLTPE or glycated VHLTPE was also quantitatively determined by HPLC-IDMS with NIM amino acid CRMs as standards. The homogeneity and stability of the CRMs were examined with a commercial HbA(1c) analyzer based on the HPLC principle. Fifteen units were randomly selected for homogeneity examination, and statistical analysis showed there was no inhomogeneity. Examination of the stability showed that the CRM was stable for at least 6 months at -80 °C. Uncertainty components of the balance, amino acid purity, hydrolysis and proteolysis efficiency, method reproducibility, homogeneity, and stability were taken into consideration for uncertainty evaluation. The certified value of NIM HbA(1c) CRM was expressed as the ratio of HbA(1c) to total hemoglobin in moles, and was (9.6 ± 1.9)%. The CRM can be used as a calibration or validation standard for clinical diagnostics. It is expected to improve the comparability for HbA(1c) measurement in China.