WorldWideScience

Sample records for reference standard method

  1. Determination of trace elements in standard reference materials by the ko-standardization method

    International Nuclear Information System (INIS)

    Smodis, B.; Jacimovic, R.; Stegnar, P.; Jovanovic, S.

    1990-01-01

    The k o -standardization method is suitable for routine multielement determinations by reactor neutron activation analysis (NAA). Investigation of NIST standard reference materials SRM 1571 Orchard Leaves, SRM 1572 Citrus leaves, and SRM 1573 Tomato Leaves showed the systematic error of 12 certified elements determined to be less than 8%. Thirty-four elements were determined in NIST proposed SRM 1515 Apple Leaves

  2. Standard Reference Tables -

    Data.gov (United States)

    Department of Transportation — The Standard Reference Tables (SRT) provide consistent reference data for the various applications that support Flight Standards Service (AFS) business processes and...

  3. Neutron activation analysis of reference materials by the k sub 0 standardization and relative methods

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, M C; Martinho, E [LNETI/ICEN, Sacavem (Portugal)

    1989-04-15

    Instrumental neutron activation analysis with the k{sub o}-standardization method was applied to eight geological, environmental and biological reference materials, including leaves, blood, fish, sediments, soils and limestone. To a first approximation, the results were normally distributed around the certified values with a standard deviation of 10%. Results obtained by using the relative method based on well characterized multi-element standards for IAEA CRM Soil-7 are reported.

  4. ANSI/ASHRAE/IES Standard 90.1-2016 Performance Rating Method Reference Manual

    Energy Technology Data Exchange (ETDEWEB)

    Goel, Supriya [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rosenberg, Michael I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Eley, Charles [Eley and Associates, Hobe Sound, FL (United States)

    2017-09-29

    This document is intended to be a reference manual for the Appendix G Performance Rating Method (PRM) of ANSI/ASHRAE/IES Standard 90.1-2016 (Standard 90.1-2016). The PRM can be used to demonstrate compliance with the standard and to rate the energy efficiency of commercial and high-rise residential buildings with designs that exceed the requirements of Standard 90.1. Use of the PRM for demonstrating compliance with Standard 90.1 is a new feature of the 2016 edition. The procedures and processes described in this manual are designed to provide consistency and accuracy by filling in gaps and providing additional details needed by users of the PRM.

  5. ANSI/ASHRAE/IES Standard 90.1-2010 Performance Rating Method Reference Manual

    Energy Technology Data Exchange (ETDEWEB)

    Goel, Supriya [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rosenberg, Michael I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-05-01

    This document is intended to be a reference manual for the Appendix G Performance Rating Method (PRM) of ANSI/ASHRAE/IES Standard 90.1- 2010 (Standard 90.1-2010).The PRM is used for rating the energy efficiency of commercial and high-rise residential buildings with designs that exceed the requirements of Standard 90.1. The procedures and processes described in this manual are designed to provide consistency and accuracy by filling in gaps and providing additional details needed by users of the PRM. It should be noted that this document is created independently from ASHRAE and SSPC 90.1 and is not sanctioned nor approved by either of those entities . Potential users of this manual include energy modelers, software developers and implementers of “beyond code” energy programs. Energy modelers using ASHRAE Standard 90.1-2010 for beyond code programs can use this document as a reference manual for interpreting requirements of the Performance Rating method. Software developers, developing tools for automated creation of the baseline model can use this reference manual as a guideline for developing the rules for the baseline model.

  6. Ozone Standard Reference Photometer

    Data.gov (United States)

    Federal Laboratory Consortium — The Standard Reference Photometer (SRP) Program began in the early 1980s as collaboration between NIST and the U.S. Environmental Protection Agency (EPA) to design,...

  7. Standard Test Method for Electrical Performance of Photovoltaic Cells Using Reference Cells Under Simulated Sunlight

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers the determination of the electrical performance of a photovoltaic cell under simulated sunlight by means of a calibrated reference cell procedure. 1.2 Electrical performance measurements are reported with respect to a select set of standard reporting conditions (SRC) (see Table 1) or to user-specified conditions. 1.2.1 The SRC or user-specified conditions include the cell temperature, the total irradiance, and the reference spectral irradiance distribution. 1.3 This test method is applicable only to photovoltaic cells with a linear response over the range of interest. 1.4 The cell parameters determined by this test method apply only at the time of test, and imply no past or future performance level. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this s...

  8. Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 This test method covers an experimental procedure for checking experimental technique and instrumentation. If followed, this test method will provide repeatable potentiostatic and potentiodynamic anodic polarization measurements that will reproduce data determined by others at other times and in other laboratories provided all laboratories are testing reference samples from the same lot of Type 430 stainless steel. 1.2 Values stated in SI units are to be regarded as the standard. Inch-pound units given in parentheses are for information only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  9. Standard Test Method for Calibration of Non-Concentrator Photovoltaic Secondary Reference Cells

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers calibration and characterization of secondary terrestrial photovoltaic reference cells to a desired reference spectral irradiance distribution. The recommended physical requirements for these reference cells are described in Specification E1040. Reference cells are principally used in the determination of the electrical performance of a photovoltaic device. 1.2 Secondary reference cells are calibrated indoors using simulated sunlight or outdoors in natural sunlight by reference to a primary reference cell previously calibrated to the same desired reference spectral irradiance distribution. 1.3 Secondary reference cells calibrated according to this test method will have the same radiometric traceability as the of the primary reference cell used for the calibration. Therefore, if the primary reference cell is traceable to the World Radiometric Reference (WRR, see Test Method E816), the resulting secondary reference cell will also be traceable to the WRR. 1.4 This test method appli...

  10. Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 These test methods cover the electrical performance of photovoltaic modules and arrays under natural or simulated sunlight using a calibrated reference cell. 1.1.1 These test methods allow a reference module to be used instead of a reference cell provided the reference module has been calibrated using these test methods against a calibrated reference cell. 1.2 Measurements under a variety of conditions are allowed; results are reported under a select set of reporting conditions (RC) to facilitate comparison of results. 1.3 These test methods apply only to nonconcentrator terrestrial modules and arrays. 1.4 The performance parameters determined by these test methods apply only at the time of the test, and imply no past or future performance level. 1.5 These test methods apply to photovoltaic modules and arrays that do not contain series-connected photovoltaic multijunction devices; such module and arrays should be tested according to Test Methods E 2236. 1.6 The values stated in SI units are to be re...

  11. Standard test method for determination of reference temperature, to, for ferritic steels in the transition range

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 This test method covers the determination of a reference temperature, To, which characterizes the fracture toughness of ferritic steels that experience onset of cleavage cracking at elastic, or elastic-plastic KJc instabilities, or both. The specific types of ferritic steels (3.2.1) covered are those with yield strengths ranging from 275 to 825 MPa (40 to 120 ksi) and weld metals, after stress-relief annealing, that have 10 % or less strength mismatch relative to that of the base metal. 1.2 The specimens covered are fatigue precracked single-edge notched bend bars, SE(B), and standard or disk-shaped compact tension specimens, C(T) or DC(T). A range of specimen sizes with proportional dimensions is recommended. The dimension on which the proportionality is based is specimen thickness. 1.3 Median KJc values tend to vary with the specimen type at a given test temperature, presumably due to constraint differences among the allowable test specimens in 1.2. The degree of KJc variability among specimen types i...

  12. A NEW APPROACH FOR CULTURING LEMNA MINOR (DUCKWEED) AND STANDARDIZED METHOD FOR USING ATRAZINE AS A REFERENCE TOXICANT

    Science.gov (United States)

    Lemna minor (Duckweed) is commonly used in aquatic toxicity investigations. Methods for culturing and testing with reference toxicants, such as atrazine, are somewhat variable among researchers. Our goal was to develop standardized methods of culturing and testing for use with L....

  13. ASTM reference radiologic digital image standards

    International Nuclear Information System (INIS)

    Wysnewski, R.; Wysnewski, D.

    1996-01-01

    ASTM Reference Radiographs have been essential in defining industry's material defect grade levels for many years. ASTM Reference Radiographs are used extensively as even the American Society for Metals Nondestructive Inspection and Quality Control Metals Handbook, Volume 11, eighth edition refers to ASTM Standard Reference Radiographs. The recently published E 1648 Standard Reference Radiographs for Examination of Aluminum Fusion Welds is a prime example of the on-going need for these references. To date, 14 Standard Reference Radiographs have been published to characterize material defects. Standard Reference Radiographs do not adequately address film-less radiologic methods. There are differences in mediums to content with. On a computer CRT defect indications appear differently when compared to indications viewed in a radiograph on a view box. Industry that uses non-film radiologic methods of inspection can be burdened with additional time and money developing internal standard reference radiologic images. These references may be deemed necessary for grading levels of product defects. Because there are no ASTM Standard Reference Radiologic data files for addressing this need in the industry, the authors of this paper suggested implementing a method for their creation under ASTM supervision. ASTM can assure continuity to those users making the transition from analog radiographic images to digital image data by swiftly addressing the requirements for reference digital image standards. The current status and possible future activities regarding a method to create digital data files is presented in this paper summary

  14. Standard Test Method for Determination of the Spectral Mismatch Parameter Between a Photovoltaic Device and a Photovoltaic Reference Cell

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers a procedure for the determination of a spectral mismatch parameter used in performance testing of photovoltaic devices. 1.2 The spectral mismatch parameter is a measure of the error, introduced in the testing of a photovoltaic device, caused by mismatch between the spectral responses of the photovoltaic device and the photovoltaic reference cell, as well as mismatch between the test light source and the reference spectral irradiance distribution to which the photovoltaic reference cell was calibrated. Examples of reference spectral irradiance distributions are Tables E490 or G173. 1.3 The spectral mismatch parameter can be used to correct photovoltaic performance data for spectral mismatch error. 1.4 This test method is intended for use with linear photovoltaic devices. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, a...

  15. Development of liquid chromatographic methods for the determination of phytosterols in Standard Reference Materials containing saw palmetto.

    Science.gov (United States)

    Bedner, Mary; Schantz, Michele M; Sander, Lane C; Sharpless, Katherine E

    2008-05-23

    Liquid chromatographic (LC) methods using atmospheric pressure chemical ionization/mass spectrometric (APCI-MS) detection were developed for the separation and analysis of the phytosterols campesterol, cycloartenol, lupenone, lupeol, beta-sitosterol, and stigmasterol. Brassicasterol and cholesterol were also included for investigation as internal standards. The methods were used to identify and quantify the phytosterols in each of two Serenoa repens (saw palmetto) Standard Reference Materials (SRMs) developed by the National Institute of Standards and Technology (NIST). Values obtained by LC-MS were compared to those obtained using the more traditional approach of gas chromatography with flame ionization detection. This is the first reported use of LC-MS to determine phytosterols in saw palmetto dietary supplement materials.

  16. Comparison between the triglycerides standardization of routine methods used in Japan and the chromotropic acid reference measurement procedure used by the CDC Lipid Standardization Programme.

    Science.gov (United States)

    Nakamura, Masakazu; Iso, Hiroyasu; Kitamura, Akihiko; Imano, Hironori; Noda, Hiroyuki; Kiyama, Masahiko; Sato, Shinichi; Yamagishi, Kazumasa; Nishimura, Kunihiro; Nakai, Michikazu; Vesper, Hubert W; Teramoto, Tamio; Miyamoto, Yoshihiro

    2016-11-01

    Background The US Centers for Disease Control and Prevention ensured adequate performance of the routine triglycerides methods used in Japan by a chromotropic acid reference measurement procedure used by the Centers for Disease Control and Prevention lipid standardization programme as a reference point. We examined standardized data to clarify the performance of routine triglycerides methods. Methods The two routine triglycerides methods were the fluorometric method of Kessler and Lederer and the enzymatic method. The methods were standardized using 495 Centers for Disease Control and Prevention reference pools with 98 different concentrations ranging between 0.37 and 5.15 mmol/L in 141 survey runs. The triglycerides criteria for laboratories which perform triglycerides analyses are used: accuracy, as bias ≤5% from the Centers for Disease Control and Prevention reference value and precision, as measured by CV, ≤5%. Results The correlation of the bias of both methods to the Centers for Disease Control and Prevention reference method was: y (%bias) = 0.516 × (Centers for Disease Control and Prevention reference value) -1.292 ( n = 495, R 2  = 0.018). Triglycerides bias at medical decision points of 1.13, 1.69 and 2.26 mmol/L was -0.71%, -0.42% and -0.13%, respectively. For the combined precision, the equation y (CV) = -0.398 × (triglycerides value) + 1.797 ( n = 495, R 2  = 0.081) was used. Precision was 1.35%, 1.12% and 0.90%, respectively. It was shown that triglycerides measurements at Osaka were stable for 36 years. Conclusions The epidemiologic laboratory in Japan met acceptable accuracy goals for 88.7% of all samples, and met acceptable precision goals for 97.8% of all samples measured through the Centers for Disease Control and Prevention lipid standardization programme and demonstrated stable results for an extended period of time.

  17. Determinations of silicon and phosphorus in Pepperbush standard reference material by neutron activation and x-ray fluorescence methods

    International Nuclear Information System (INIS)

    Mizumoto, Yoshihiko; Nishio, Hirofumi; Hayashi, Takeshi; Kusakabe, Toshio; Iwata, Shiro.

    1987-01-01

    Silicon and phosphorus contents in Pepperbush standard reference material were determined by neutron activation and X-ray fluorescence methods. In neutron activation analysis, β-ray spectra of 32 P produced by 31 P(n,γ) 32 P reaction on Pepperbush and standard samples were measured by a low background β-ray spectrometer. In X-ray fluorescence analysis, the standard samples were prepared by mixing the Pepperbush powder with silicon dioxide and diammonium hydrogenphosphate. Characteristic X-rays from the samples were analyzed by a wavelength dispersive X-ray fluorescence spectrometer. From the β and X-ray intensities, silicon and phosphorus contents in Pepperbush were determined to be 1840 ± 80 and 1200 ± 50 μg g -1 , respectively. (author)

  18. 40 CFR 98.7 - What standardized methods are incorporated by reference into this part?

    Science.gov (United States)

    2010-07-01

    ... Hydraulic Cement, IBR approved for §§ 98.84(a), 98.84(b), and 98.84(c). (3) ASTM D235-02 (Reapproved 2007... Method for Density, Relative Density (Specific Gravity), or API Gravity of Crude Petroleum and Liquid..., Compressibility Factor, and Relative Density of Gaseous Fuels, IBR approved for §§ 98.34(a) and 98.254(e). (21...

  19. Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method is intended to be used for calibration and characterization of primary terrestrial photovoltaic reference cells to a desired reference spectral irradiance distribution, such as Tables G173. The recommended physical requirements for these reference cells are described in Specification E1040. Reference cells are principally used in the determination of the electrical performance of photovoltaic devices. 1.2 Primary photovoltaic reference cells are calibrated in natural sunlight using the relative spectral response of the cell, the relative spectral distribution of the sunlight, and a tabulated reference spectral irradiance distribution. 1.3 This test method requires the use of a pyrheliometer that is calibrated according to Test Method E816, which requires the use of a pyrheliometer that is traceable to the World Radiometric Reference (WRR). Therefore, reference cells calibrated according to this test method are traceable to the WRR. 1.4 This test method is a technique that may be used ...

  20. Standardization of glycohemoglobin results and reference values in whole blood studied in 103 laboratories using 20 methods.

    Science.gov (United States)

    Weykamp, C W; Penders, T J; Miedema, K; Muskiet, F A; van der Slik, W

    1995-01-01

    We investigated the effect of calibration with lyophilized calibrators on whole-blood glycohemoglobin (glyHb) results. One hundred three laboratories, using 20 different methods, determined glyHb in two lyophilized calibrators and two whole-blood samples. For whole-blood samples with low (5%) and high (9%) glyHb percentages, respectively, calibration decreased overall interlaboratory variation (CV) from 16% to 9% and from 11% to 6% and decreased intermethod variation from 14% to 6% and from 12% to 5%. Forty-seven laboratories, using 14 different methods, determined mean glyHb percentages in self-selected groups of 10 nondiabetic volunteers each. With calibration their overall mean (2SD) was 5.0% (0.5%), very close to the 5.0% (0.3%) derived from the reference method used in the Diabetes Control and Complications Trial. In both experiments the Abbott IMx and Vision showed deviating results. We conclude that, irrespective of the analytical method used, calibration enables standardization of glyHb results, reference values, and interpretation criteria.

  1. Recent applications of nuclear analytical methods to the certification of elemental content in NIST standard reference materials

    International Nuclear Information System (INIS)

    Greenberg, R.R.; Zeisler, R.; Mackey, E.A.

    2006-01-01

    Well-characterized, certified reference materials (CRMs) play an essential role in assuring the quality of analytical measurements. NIST has been producing CRMs, currently called NIST Standard Reference Materials (SRMs), to validate analytical measurements for nearly one hundred years. The predominant mode of certifying inorganic constituents in complex-matrix SRMs is through the use of two critically evaluated, independent analytical techniques at NIST. These techniques should have no significant sources of error in common. The use of nuclear analytical methods in combination with one of the chemically based analytical method at NIST eliminates the possibility of any significant, common error source. The inherent characteristics of the various forms of nuclear analytical methods make them extremely valuable for SRM certification. Instrumental NAA is nondestructive, which eliminates the possibility of any dissolution problems, and often provides homogeneity information. Radiochemical NAA typically provides nearly blank-free determinations of some highly important, but difficult elements at very low levels. Prompt-gamma NAA complements INAA, and provides independent determinations of some key elements. In addition, all significant uncertainty components can be evaluated for these techniques, and we believe these methods can meet all the requirements of a primary method of measurement as defined by ISO and the CCQM. NIST has certified several SRMs using INAA and RNAA as primary methods. In addition, NIST has compared measurements by INAA and PGAA with other primary methods as part of the CCQM intercomparisons of national metrology institutes. Some significant SRMs recently certified for inorganic constituents with contributions from the nuclear analytical methods include: Toxic Substances in Urine (SRM 2670a), Lake Superior Fish Tissue (SRM 1946), Air Particulate on Filter Media (SRM 2783), Inorganics in Marine Sediment (SRM 2702), Sediment for Solid Sampling (Small

  2. A comparative uncertainty study of the calibration of macrolide antibiotic reference standards using quantitative nuclear magnetic resonance and mass balance methods

    International Nuclear Information System (INIS)

    Liu Shuyu; Hu Changqin

    2007-01-01

    This study introduces the general method of quantitative nuclear magnetic resonance (qNMR) for the calibration of reference standards of macrolide antibiotics. Several qNMR experimental conditions were optimized including delay, which is an important parameter of quantification. Three kinds of macrolide antibiotics were used to validate the accuracy of the qNMR method by comparison with the results obtained by the high performance liquid chromatography (HPLC) method. The purities of five common reference standards of macrolide antibiotics were measured by the 1 H qNMR method and the mass balance method, respectively. The analysis results of the two methods were compared. The qNMR is quick and simple to use. In a new medicine research and development process, qNMR provides a new and reliable method for purity analysis of the reference standard

  3. Development of standard reference samples for diffractometry

    International Nuclear Information System (INIS)

    Galvao, Antonio de Sant'Ana

    2011-01-01

    In this work, samples of standard reference materials for diffractometry of polycrystals were developed. High-purity materials were submitted to mechanical and thermal treatments in order to present the adequate properties to be used as high-quality standard reference materials for powder diffraction, comparable to the internationally recognized produced by the USA National Institute of Standards and Technology NIST, but at lower costs. The characterization of the standard materials was performed by measurements in conventional X-ray diffraction diffractometers, high resolution neutron diffraction and high-resolution synchrotron diffraction. The lattice parameters were calculated by extrapolation of the values obtained from each X-ray reflection against cos 2 θ by the Least-Squares Method. The adjustments were compared to the values obtained by the Rietveld Method, using program GSAS. The materials thus obtained were the α-alumina, yttrium oxide, silicon, cerium oxide, lanthanum hexaboride and lithium fluoride. The standard reference materials produced present quality similar or, in some cases, superior to the standard reference materials produced and commercialized by the NIST. (author)

  4. Determination of reference intervals and comparison of venous blood gas parameters using standard and non-standard collection methods in 24 cats.

    Science.gov (United States)

    Bachmann, Karin; Kutter, Annette Pn; Schefer, Rahel Jud; Marly-Voquer, Charlotte; Sigrist, Nadja

    2017-08-01

    Objectives The aim of this study was to determine in-house reference intervals (RIs) for venous blood analysis with the RAPIDPoint 500 blood gas analyser using blood gas syringes (BGSs) and to determine whether immediate analysis of venous blood collected into lithium heparin (LH) tubes can replace anaerobic blood sampling into BGSs. Methods Venous blood was collected from 24 healthy cats and directly transferred into a BGS and an LH tube. The BGS was immediately analysed on the RAPIDPoint 500 followed by the LH tube. The BGSs and LH tubes were compared using paired t-test or Wilcoxon matched-pairs signed-rank test, Bland-Altman and Passing-Bablok analysis. To assess clinical relevance, bias or percentage bias between BGSs and LH tubes was compared with the allowable total error (TEa) recommended for the respective parameter. Results Based on the values obtained from the BGSs, RIs were calculated for the evaluated parameters, including blood gases, electrolytes, glucose and lactate. Values derived from LH tubes showed no significant difference for standard bicarbonate, whole blood base excess, haematocrit, total haemoglobin, sodium, potassium, chloride, glucose and lactate, while pH, partial pressure of carbon dioxide and oxygen, actual bicarbonate, extracellular base excess, ionised calcium and anion gap were significantly different to the samples collected in BGSs ( P glucose and lactate can be made based on blood collected in LH tubes and analysed within 5 mins. For pH, partial pressure of carbon dioxide and oxygen, extracellular base excess, anion gap and ionised calcium the clinically relevant alterations have to be considered if analysed in LH tubes.

  5. Comparison study for the CCME reference method for determination of PHC in soil by using internal and external standard methods and by using silica gel column cleanup and in-situ silica gel cleanup methods

    International Nuclear Information System (INIS)

    Wang, Z.; Fingas, M.; Sigouin, L.; Yang, C.; Hollebone, B.

    2003-01-01

    The assessment, cleanup, and remediation of hydrocarbon contaminated sites is covered in the Reference Method for Canada-Wide Standard for Petroleum Hydrocarbons-Tier 1 Method. It replaces several analytical methods used in the past by some laboratories and jurisdictions in Canada. The authors conducted two comparative evaluations to validate the Tier 1 Analytical Method. The first compared the Internal and External Standard Methods, and the second compared the Silica Gel Column Cleanup Method with the In-situ Silica Gel Cleanup Method. The Canadian Council of Ministers of the Environment (CCME) Tier 1 Method recommends and requires the External Standard Method to determine petroleum hydrocarbons (PHC) in soil samples. The Internal Method is widely used to quantify various organic and inorganic pollutants in environmental samples. The Tier 1 Method offers two options for the same extract cleanup. They are: Option A - In-situ Silica Gel Cleanup, and Option B - Silica Gel Column Cleanup. Linearity, precision, and PHC quantification results were the parameters considered for diesel and motor oil solutions, for diesel spiked soil samples, and for motor oil spiked soil samples. It was concluded that both the External and Internal Standard Methods for gas chromatograph (GC) determination of PHC in soil possess their own advantages. The PHC results obtained using the In-Situ Silica Gel Cleanup Method were lower than those obtained with the Silica Gel Column Cleanup Methods. The more efficient and effective sample cleanup method proved to be the Silica Gel Column Method. 13 refs., 7 tabs., 7 figs

  6. Standard digital reference images for titanium castings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 The digital reference images provided in the adjunct to this standard illustrate various types and degrees of discontinuities occurring in titanium castings. Use of this standard for the specification or grading of castings requires procurement of the adjunct digital reference images, which illustrate the discontinuity types and severity levels. They are intended to provide the following: 1.1.1 A guide enabling recognition of titanium casting discontinuities and their differentiation both as to type and degree through digital radiographic examination. 1.1.2 Example digital radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications and drawings. 1.2 The digital reference images consist of seventeen digital files each illustrating eight grades of increasing severity. The files illustrate seven common discontinuity types representing casting sections up to 1-in. (25.4-mm). 1.3 The reference radiographs were developed for casting sections up to 1...

  7. Electrothermal frequency references in standard CMOS

    CERN Document Server

    Kashmiri, S Mahdi

    2013-01-01

    This book describes an alternative method of accurate on-chip frequency generation in standard CMOS IC processes. This method exploits the thermal-diffusivity of silicon, the rate at which heat diffuses through a silicon substrate.  This is the first book describing thermal-diffusivity-based frequency references, including the complete theoretical methodology supported by practical realizations that prove the feasibility of the method.  Coverage also includes several circuit and system-level solutions for the analog electronic circuit design challenges faced.   ·         Surveys the state-of-the-art in all-silicon frequency references; ·         Examines the thermal properties of silicon as a solution for the challenge of on-chip accurate frequency generation; ·         Uses simplified modeling approaches that allow an electronics engineer easily to simulate the electrothermal elements; ·         Follows a top-down methodology in circuit design, in which system-level des...

  8. Quantification of pneumothorax volume on chest radiographs: comparison between the collins' and the axel's methods with three-dimensional CT as the standard of reference

    International Nuclear Information System (INIS)

    Lee, Chang Keun; Kim, Hyung Jin; Lee, Kyung Hee; Kim, Joung Taek; Kim, Kwang Ho; Suh, Chang Hae; Han, Heon

    1999-01-01

    The purpose of this study was twofold. In a preliminary study, we evaluated the accuracy of 3-D (three-dimensional) CT for the estimation of pneumothorax volume and for providing the optimal postprocessing method for clinical study. In the clinical study, we determined which of the two methods, Collins' and Axel's, was more accurate for the estimation of pneumothorax volume, as seen on chest radiographs, using 3-D CT as the standard of reference. In the preliminary study, 3-D CT was applied to phantoms and to four patients with pneumothorax using two different postprocessing methods, manual contour delineation and thresholding. In the clinical study, 3-D CT was performed in 13 patients with pneumothorax. For the purpose of evaluating conventional radiographs, a localizer scan was used for comparing the accuracy of Collins' method with that of Axel's method, with 3-D CT as the standard of reference. The preliminary study revealed that 3-D CT estimated pneumothorax volume with great accuracy and that manual contour delineation and thresholding measured volume equally well. Because of the shorter postprocessing time required with thresholding than with manual contour delineation (5 min versus 30 min), the former was used during clinical study. The results of this indicated close correlation between the measurements obtained using Collins' method on chest radiographs and those obtained by 3-D CT(r=0.95, p 0.05). 3-D CT can estimate pneumothorax volume with great accuracy. Collins' method is superior to Axel's method for the quantification of pneumothorax volume as seen on chest radiographs

  9. STANDARDIZATION OF GLYCOHEMOGLOBIN RESULTS AND REFERENCE VALUES IN WHOLE-BLOOD STUDIED IN 103 LABORATORIES USING 20 METHODS

    NARCIS (Netherlands)

    WEYKAMP, CW; PENDERS, TJ; MUSKIET, FAJ; VANDERSLIK, W

    We investigated the effect of calibration with lyophilized calibrators on whole-blood glycohemoglobin (glyHb) results. One hundred three laboratories, using 20 different methods, determined glyHb in two lyophilized calibrators and two whole-blood samples. For whole-blood samples with low (5%) and

  10. The evaluation of accuracy of NAA method used by P2TRR laboratory with food standard reference material analysis

    International Nuclear Information System (INIS)

    Rina M, Th.; Sri-Wardhani; Sunarko

    2003-01-01

    The NAA method is the analysis method with high precision and accuracy level. The precision and accuracy of NAA laboratory in P2TRR had been evaluated with SRM 1573a Tomato Leaf and CRM No.9 Sargasso. Samples were irradiated in RSG-GAS's rabbit system and counted with gamma spectrometry. The results obtained from this research are for the SRM 1573a sample the test could analyze 17 elements of the 40 certified elements, and for CRM No.9 sample the test could analyze 16 elements of the 30 certified elements. The result of quantitative analysis indicate the different deviation of each element between 2 -10.5 % compared to the certificate data. This deviation value <15%, this value shows that the precision and accuracy level is good enough

  11. 15 CFR 230.3 - New Standard Reference Materials.

    Science.gov (United States)

    2010-01-01

    ... NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, DEPARTMENT OF COMMERCE STANDARD REFERENCE MATERIALS STANDARD REFERENCE MATERIALS General Information § 230.3 New Standard Reference Materials. When new SRM's... scientific and trade journals. ...

  12. Practical reference - radiation standards in Canada

    International Nuclear Information System (INIS)

    1983-07-01

    In developing a policy that will require licensees to calibrate their radiation dose measuring devices and trace such calibrations to approved reference standards, the AECB has consulted recognized experts. This document presents the experts' reports and recommendations which will be considered in finalizing the policy

  13. Use of fat mass and fat free mass standard deviation scores obtained using simple measurement methods in healthy children and patients: comparison with the reference 4-component model.

    Science.gov (United States)

    Atherton, Rachel R; Williams, Jane E; Wells, Jonathan C K; Fewtrell, Mary S

    2013-01-01

    Clinical application of body composition (BC) measurements for individual children has been limited by lack of appropriate reference data. (1) To compare fat mass (FM) and fat free mass (FFM) standard deviation scores (SDS) generated using new body composition reference data and obtained using simple measurement methods in healthy children and patients with those obtained using the reference 4-component (4-C) model; (2) To determine the extent to which scores from simple methods agree with those from the 4-C model in identification of abnormal body composition. FM SDS were calculated for 4-C model, dual-energy X-ray absorptiometry (DXA; GE Lunar Prodigy), BMI and skinfold thicknesses (SFT); and FFM SDS for 4CM, DXA and bioelectrical impedance analysis (BIA; height(2)/Z)) in 927 subjects aged 3.8-22.0 y (211 healthy, 716 patients). DXA was the most accurate method for both FM and FFM SDS in healthy subjects and patients (mean bias (limits of agreement) FM SDS 0.03 (± 0.62); FFM SDS -0.04 (± 0.72)), and provided best agreement with the 4-C model in identifying abnormal BC (SDS ≤-2 or ≥ 2). BMI and SFTs were reasonable predictors of abnormal FM SDS, but poor in providing an absolute value. BIA was comparable to DXA for FFM SDS and in identifying abnormal subjects. DXA may be used both for research and clinically to determine FM and FFM SDS. BIA may be used to assess FFM SDS in place of DXA. BMI and SFTs can be used to measure adiposity for groups but not individuals. The performance of simpler techniques in monitoring longitudinal BC changes requires investigation. Ultimately, the most appropriate method should be determined by its predictive value for clinical outcome.

  14. Use of fat mass and fat free mass standard deviation scores obtained using simple measurement methods in healthy children and patients: comparison with the reference 4-component model.

    Directory of Open Access Journals (Sweden)

    Rachel R Atherton

    Full Text Available BACKGROUND: Clinical application of body composition (BC measurements for individual children has been limited by lack of appropriate reference data. OBJECTIVES: (1 To compare fat mass (FM and fat free mass (FFM standard deviation scores (SDS generated using new body composition reference data and obtained using simple measurement methods in healthy children and patients with those obtained using the reference 4-component (4-C model; (2 To determine the extent to which scores from simple methods agree with those from the 4-C model in identification of abnormal body composition. DESIGN: FM SDS were calculated for 4-C model, dual-energy X-ray absorptiometry (DXA; GE Lunar Prodigy, BMI and skinfold thicknesses (SFT; and FFM SDS for 4CM, DXA and bioelectrical impedance analysis (BIA; height(2/Z in 927 subjects aged 3.8-22.0 y (211 healthy, 716 patients. RESULTS: DXA was the most accurate method for both FM and FFM SDS in healthy subjects and patients (mean bias (limits of agreement FM SDS 0.03 (± 0.62; FFM SDS -0.04 (± 0.72, and provided best agreement with the 4-C model in identifying abnormal BC (SDS ≤-2 or ≥ 2. BMI and SFTs were reasonable predictors of abnormal FM SDS, but poor in providing an absolute value. BIA was comparable to DXA for FFM SDS and in identifying abnormal subjects. CONCLUSIONS: DXA may be used both for research and clinically to determine FM and FFM SDS. BIA may be used to assess FFM SDS in place of DXA. BMI and SFTs can be used to measure adiposity for groups but not individuals. The performance of simpler techniques in monitoring longitudinal BC changes requires investigation. Ultimately, the most appropriate method should be determined by its predictive value for clinical outcome.

  15. Thermal-Diffusivity-Based Frequency References in Standard CMOS

    NARCIS (Netherlands)

    Kashmiri, S.M.

    2012-01-01

    In recent years, a lot of research has been devoted to the realization of accurate integrated frequency references. A thermal-diffusivity-based (TD) frequency reference provides an alternative method of on-chip frequency generation in standard CMOS technology. A frequency-locked loop locks the

  16. ENAA of iodine in standard reference material lyophilized human urine

    International Nuclear Information System (INIS)

    Zhang Yongbao; Wang Ke; Wang Ganfeng

    1997-01-01

    The contents of iodine in two kinds of standard reference materials lyophilized human urine are determined by ENAA. The sensitivity of this method is ten times higher than that of TNAA, and the relative standard deviations of ten measurements are 2.9% and 3.3%, respectively. Two certificated reference samples are used for verification of the analysis. The analytical results are in agreement with the recommended values, and the relative error is less than 3%

  17. Agreement between gastrointestinal panel testing and standard microbiology methods for detecting pathogens in suspected infectious gastroenteritis: Test evaluation and meta-analysis in the absence of a reference standard.

    Science.gov (United States)

    Freeman, Karoline; Tsertsvadze, Alexander; Taylor-Phillips, Sian; McCarthy, Noel; Mistry, Hema; Manuel, Rohini; Mason, James

    2017-01-01

    Multiplex gastrointestinal pathogen panel (GPP) tests simultaneously identify bacterial, viral and parasitic pathogens from the stool samples of patients with suspected infectious gastroenteritis presenting in hospital or the community. We undertook a systematic review to compare the accuracy of GPP tests with standard microbiology techniques. Searches in Medline, Embase, Web of Science and the Cochrane library were undertaken from inception to January 2016. Eligible studies compared GPP tests with standard microbiology techniques in patients with suspected gastroenteritis. Quality assessment of included studies used tailored QUADAS-2. In the absence of a reference standard we analysed test performance taking GPP tests and standard microbiology techniques in turn as the benchmark test, using random effects meta-analysis of proportions. No study provided an adequate reference standard with which to compare the test accuracy of GPP and conventional tests. Ten studies informed a meta-analysis of positive and negative agreement. Positive agreement across all pathogens was 0.93 (95% CI 0.90 to 0.96) when conventional methods were the benchmark and 0.68 (95% CI: 0.58 to 0.77) when GPP provided the benchmark. Negative agreement was high in both instances due to the high proportion of negative cases. GPP testing produced a greater number of pathogen-positive findings than conventional testing. It is unclear whether these additional 'positives' are clinically important. GPP testing has the potential to simplify testing and accelerate reporting when compared to conventional microbiology methods. However the impact of GPP testing upon the management, treatment and outcome of patients is poorly understood and further studies are needed to evaluate the health economic impact of GPP testing compared with standard methods. The review protocol is registered with PROSPERO as CRD42016033320.

  18. Fabricating defensible reference standards for the NDA lab

    Energy Technology Data Exchange (ETDEWEB)

    Ceo, R.N.; May, P.K. [Oak Ridge Y-12 Plant, TN (United States)

    1997-11-01

    Nondestructive analysis (NDA) is performed at the Oak Ridge Y-12 Plant in support of the enriched uranium operations. Process materials are analyzed using gamma ray- and neutron-based instruments including segmented gamma scanners, solution assay systems, and an active well coincidence counter. Process wastes are also discarded based on results of these measurements. Good analytical practice, as well as applicable regulations, mandates that these analytical methods be calibrated using reference materials traceable to the national standards base. Reference standards for NDA instruments are not commercially available owing to the large quantities of special nuclear materials involved. Instead, representative materials are selected from each process stream, then thoroughly characterized by methods that are traceable to the national standards base. This paper discusses the process materials to be analyzed, reference materials selected for calibrating each NDA instrument, and details of their characterization and fabrication into working calibrations standards. Example calibration curves are also presented. 4 figs.

  19. Fabricating defensible reference standards for the NDA lab

    International Nuclear Information System (INIS)

    Ceo, R.N.; May, P.K.

    1997-01-01

    Nondestructive analysis (NDA) is performed at the Oak Ridge Y-12 Plant in support of the enriched uranium operations. Process materials are analyzed using gamma ray- and neutron-based instruments including segmented gamma scanners, solution assay systems, and an active well coincidence counter. Process wastes are also discarded based on results of these measurements. Good analytical practice, as well as applicable regulations, mandates that these analytical methods be calibrated using reference materials traceable to the national standards base. Reference standards for NDA instruments are not commercially available owing to the large quantities of special nuclear materials involved. Instead, representative materials are selected from each process stream, then thoroughly characterized by methods that are traceable to the national standards base. This paper discusses the process materials to be analyzed, reference materials selected for calibrating each NDA instrument, and details of their characterization and fabrication into working calibrations standards. Example calibration curves are also presented. 4 figs

  20. Standards for reference reactor physics measurements

    International Nuclear Information System (INIS)

    Harris, D.R.; Cokinos, D.M.; Uotinen, V.

    1990-01-01

    Reactor physics analysis methods require experimental testing and confirmation over the range of practical reactor configurations and states. This range is somewhat limited by practical fuel types such as actinide oxides or carbides enclosed in metal cladding. On the other hand, this range continues to broaden because of the trend of using higher enrichment, if only slightly enriched, electric utility fuel. The need for experimental testing of the reactor physics analysis methods arises in part because of the continual broadening of the range of core designs, and in part because of the nature of the analysis methods. Reactor physics analyses are directed primarily at the determination of core reactivities and reaction rates, the former largely for reasons of reactor control, and the latter largely to ensure that material limitations are not violated. Errors in these analyses can be regarded as being from numerics, from the data base, and from human factors. For numerical, data base, and human factor reasons, then, it is prudent and customary to qualify reactor physical analysis methods against experiments. These experiments can be treated as being at low power or at high power, and each of these types is subject to an American National Standards Institute standard. The purpose of these standards is to aid in improving and maintaining adequate quality in reactor physics methods, and it is from this point of view that the standards are examined here

  1. Actual survey of dose evaluation method for standardization of radiation therapy techniques. With special reference to display method of radiation doses

    International Nuclear Information System (INIS)

    Kumagai, Kozo; Yoshiura, Takao; Izumi, Takashi; Araki, Fujio; Takada, Takuo; Jingu, Kenichi.

    1994-01-01

    This report presents the results of questionnaire survey for actual conditions of radiation therapy, which was conducted with the aim of establishing the standardization of radiation therapy techniques. Questionnaires were sent to 100 facilities in Japan, and 86 of these answered, consisting of 62 university hospitals, 2 national hospitals, 14 cancer centers, 4 prefectural or municipal hospitals, and 4 other hospitals. In addition to electron beam therapy, the following typical diseases for radiation therapy were selected as standard irradiation models: cancers of the larynx, esophagus, breast, and uterine cervix, and malignant lymphomas. According to these models, questionnaire results are analyzed in terms of the following four items: (1) irradiation procedures, (2) energy used for radiotherapy, (3) the depth for calculating target absorption doses, and (4) points for displaying target absorption doses. (N.K.)

  2. Strategies for building reference standards for autoantibodies

    Directory of Open Access Journals (Sweden)

    Joanna eSheldon

    2015-04-01

    Full Text Available Producing robust, certified, traceable reference material for autoantibody testing is a vital element in maintaining the validity of results that are generated in the daily clinical laboratory routine. This is a huge challenge because of the high number of variables involved in the detection and measurement of the autoantibodies. The production of such materials is time consuming and needs rigorous attention to detail; this is best achieved by an overarching independent body who will oversee the process in a not for profit manner.Much effort has been made to build international standards for quantitative and qualitative assays based on monoclonal antibodies, obtained from affinity purification and plasmapheresis. The big challenge is to respect individual differences in immune response to the same antigen. A promising ongoing initiative is the construction of pools with monospecific samples from different individuals.

  3. Newly developed standard reference materials for organic contaminant analysis

    Energy Technology Data Exchange (ETDEWEB)

    Poster, D.; Kucklick, J.; Schantz, M.; Porter, B.; Wise, S. [National Inst. of Stand. and Technol., Gaithersburg, MD (USA). Center for Anal. Chem.

    2004-09-15

    The National Institute of Standards and Technology (NIST) has issued a number of Standard Reference Materials (SRM) for specified analytes. The SRMs are biota and biological related materials, sediments and particle related SRMs. The certified compounds for analysis are polychlorinated biphenyls (PCB), polycylic aromatic hydrocarbons (PAH) and their nitro-analogues, chlorinated pesticides, methylmercury, organic tin compounds, fatty acids, polybrominated biphenyl ethers (PBDE). The authors report on origin of materials and analytic methods. (uke)

  4. 78 FR 13243 - Updates to Standards Incorporated by Reference; Reapproved ASTM Standards; Technical Amendment

    Science.gov (United States)

    2013-02-27

    ... Characteristics of Plastic Film 2009)[egr]1. and Sheeting. Standard Specification for F682-82a F682-82a 46 56.01-2... (Reapproved Standard Test Method for Determining Gas 2009)[egr]1. Permeability Characteristics of Plastic Film... Permeability Characteristics of Plastic Film and Sheeting (approved May 1, 2009), incorporation by reference...

  5. Halogens determination in vegetable NBS standard reference materials

    International Nuclear Information System (INIS)

    Stella, R.; Genova, N.; Di Casa, M.

    1977-01-01

    Levels of all four halogens in Orchard Leaves, Pine Needles and Tomato Leaves NBS reference standards were determined. For fluorine a spiking isotope dilution method was used followed by HF absorption on glass beads. Instrumental nuclear activation analysis was adopted for chlorine and bromine determination. Radiochemical separation by a distillation procedure was necessary for iodine nuclear activation analysis after irradiation. Activation parameters of Cl, Br and I are reported. Results of five determinations for each halogen in Orchard Leaves, Pine Needles and Tomato Leaves NBS Standard Materials and Standard deviations of the mean are reported. (T.I.)

  6. Characterization of the NIST shellfish Standard Reference Material 4358

    International Nuclear Information System (INIS)

    Nour, S.; Inn, K.G.W.; Filliben, J.; Gaast van der, H.; Men, L.C.; Calmet, D.; Altzitzoglou, T.; Povinec, P.; Takata, Y.; Wisdom, M.

    2013-01-01

    A new shellfish Standard Reference Material 4358 was developed by the National Institute of Standards and Technology through an international interlaboratory comparison that involved twelve laboratories-participants from nine countries. The results from the participants were statistically evaluated, and the most robust certified values were based on the median of laboratories’ reported means and the uncertainties derived using the bootstrap method. Massic activity certified values were established for fourteen radionuclides, five activity ratios, and informational massic activity values for eight more radionuclides and two activity ratios. (author)

  7. Determination of polybrominated diphenyl ethers in environmental standard reference materials

    Energy Technology Data Exchange (ETDEWEB)

    Stapleton, Heather M.; Schantz, Michele M.; Wise, Stephen A. [National Institute of Standards and Technology, Analytical Chemistry Division, Gaithersburg, MD (United States); Keller, Jennifer M.; Kucklick, John R. [National Institute of Standards and Technology, Analytical Chemistry Division, Hollings Marine Laboratory, Charleston, SC (United States); Leigh, Stefan D. [National Institute of Standards and Technology, Statistical Engineering Division, Gaithersburg, MD (United States)

    2007-04-15

    Standard reference materials (SRMs) are valuable tools in developing and validating analytical methods to improve quality assurance standards. The National Institute of Standards and Technology (NIST) has a long history of providing environmental SRMs with certified concentrations of organic and inorganic contaminants. Here we report on new certified and reference concentrations for 27 polybrominated diphenyl ether (PBDE) congeners in seven different SRMs: cod-liver oil, whale blubber, fish tissue (two materials), mussel tissue and sediment (two materials). PBDEs were measured in these SRMs, with the lowest concentrations measured in mussel tissue (SRM 1974b) and the highest in sediment collected from the New York/New Jersey Waterway (SRM 1944). Comparing the relative PBDE congener concentrations within the samples, we found the biota SRMs contained primarily tetrabrominated and pentabrominated diphenyl ethers, whereas the sediment SRMs contained primarily decabromodiphenyl ether (BDE 209). The cod-liver oil (SRM 1588b) and whale blubber (SRM 1945) materials were also found to contain measurable concentrations of two methoxylated PBDEs (MeO-BDEs). Certified and reference concentrations are reported for 12 PBDE congeners measured in the biota SRMs and reference values are available for two MeO-BDEs. Results from a sediment interlaboratory comparison PBDE exercise are available for the two sediment SRMs (1941b and 1944). (orig.)

  8. Generation of gaseous methanol reference standards

    International Nuclear Information System (INIS)

    Geib, R.C.

    1991-01-01

    Methanol has been proposed as an automotive fuel component. Reliable, accurate methanol standards are essential to support widespread monitoring programs. The monitoring programs may include quantification of methanol from tailpipe emissions, evaporative emissions, plus ambient air methanol measurements. This paper will present approaches and results in the author's investigation to develop high accuracy methanol standards. The variables upon which the authors will report results are as follows: (1) stability of methanol gas standards, the studies will focus on preparation requirements and stability results from 10 to 1,000 ppmv; (2) cylinder to instrument delivery system components and purge technique, these studies have dealt with materials in contact with the sample stream plus static versus flow injection; (3) optimization of gas chromatographic analytical system will be discussed; (4) gas chromatography and process analyzer results and utility for methanol analysis will be presented; (5) the accuracy of the methanol standards will be qualified using data from multiple studies including: (a) gravimetric preparation; (b) linearity studies; (c) independent standards sources such as low pressure containers and diffusion tubes. The accuracy will be provided as a propagation of error from multiple sources. The methanol target concentrations will be 10 to 500 ppmv

  9. 15 CFR 200.105 - Standard reference data.

    Science.gov (United States)

    2010-01-01

    ... for application in energy, environment and health, industrial process design, materials durability... application in research, development, engineering design, and commerce. The Office of Standard Reference Data...

  10. Standard Reference Development of nuclear material for Tensile and Hardness Test Properties

    International Nuclear Information System (INIS)

    Choo, Y. S.; Kim, D. S.; Yoo, B. O.; Ahn, S. B.; Baik, S. J.; Chun, Y. B.; Kim, K. H.; Hong, K. P.; Ryu, W. S.

    2007-12-01

    Standard reference is a official approved data such a coefficient of physics, approved material properties, and etc., which should be analyzed and evaluated by scientific method to acquire official approval for accuracy and credibility of measured data and information. So it could be used broadly and continuously by various fields of nation and society. It is classified to effective standard reference, verified standard reference, and certified standard reference. There are sixteen fields in designated standard references such a physical chemistry field, material field, metal field, and the others. The standard reference of neutron irradiated nuclear structural material is classified to metal field. This report summarized the whole processes about data collection, data production, data evaluation and the suggestion of details evaluation technical standard for tensile and hardness properties, which were achieved by carry out the project 'nuclear material standard reference development' as a result

  11. Standard Reference Development of nuclear material for Tensile and Hardness Test Properties

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Y. S.; Kim, D. S.; Yoo, B. O.; Ahn, S. B.; Baik, S. J.; Chun, Y. B.; Kim, K. H.; Hong, K. P.; Ryu, W. S

    2007-12-15

    Standard reference is a official approved data such a coefficient of physics, approved material properties, and etc., which should be analyzed and evaluated by scientific method to acquire official approval for accuracy and credibility of measured data and information. So it could be used broadly and continuously by various fields of nation and society. It is classified to effective standard reference, verified standard reference, and certified standard reference. There are sixteen fields in designated standard references such a physical chemistry field, material field, metal field, and the others. The standard reference of neutron irradiated nuclear structural material is classified to metal field. This report summarized the whole processes about data collection, data production, data evaluation and the suggestion of details evaluation technical standard for tensile and hardness properties, which were achieved by carry out the project 'nuclear material standard reference development' as a result.

  12. Standardized waste form test methods

    International Nuclear Information System (INIS)

    Slate, S.C.

    1984-11-01

    The Materials Characterization Center (MCC) is developing standard tests to characterize nuclear waste forms. Development of the first thirteen tests was originally initiated to provide data to compare different high-level waste (HLW) forms and to characterize their basic performance. The current status of the first thirteen MCC tests and some sample test results is presented: The radiation stability tests (MCC-6 and 12) and the tensile-strength test (MCC-11) are approved; the static leach tests (MCC-1, 2, and 3) are being reviewed for full approval; the thermal stability (MCC-7) and microstructure evaluation (MCC-13) methods are being considered for the first time; and the flowing leach tests methods (MCC-4 and 5), the gas generation methods (MCC-8 and 9), and the brittle fracture method (MCC-10) are indefinitely delayed. Sample static leach test data on the ARM-1 approved reference material are presented. Established tests and proposed new tests will be used to meet new testing needs. For waste form production, tests on stability and composition measurement are needed to provide data to ensure waste form quality. In transportation, data are needed to evaluate the effects of accidents on canisterized waste forms. The new MCC-15 accident test method and some data are presented. Compliance testing needs required by the recent draft repository waste acceptance specifications are described. These specifications will control waste form contents, processing, and performance. 2 references, 2 figures

  13. Standard setting: Comparison of two methods

    Directory of Open Access Journals (Sweden)

    Oyebode Femi

    2006-09-01

    Full Text Available Abstract Background The outcome of assessments is determined by the standard-setting method used. There is a wide range of standard – setting methods and the two used most extensively in undergraduate medical education in the UK are the norm-reference and the criterion-reference methods. The aims of the study were to compare these two standard-setting methods for a multiple-choice question examination and to estimate the test-retest and inter-rater reliability of the modified Angoff method. Methods The norm – reference method of standard -setting (mean minus 1 SD was applied to the 'raw' scores of 78 4th-year medical students on a multiple-choice examination (MCQ. Two panels of raters also set the standard using the modified Angoff method for the same multiple-choice question paper on two occasions (6 months apart. We compared the pass/fail rates derived from the norm reference and the Angoff methods and also assessed the test-retest and inter-rater reliability of the modified Angoff method. Results The pass rate with the norm-reference method was 85% (66/78 and that by the Angoff method was 100% (78 out of 78. The percentage agreement between Angoff method and norm-reference was 78% (95% CI 69% – 87%. The modified Angoff method had an inter-rater reliability of 0.81 – 0.82 and a test-retest reliability of 0.59–0.74. Conclusion There were significant differences in the outcomes of these two standard-setting methods, as shown by the difference in the proportion of candidates that passed and failed the assessment. The modified Angoff method was found to have good inter-rater reliability and moderate test-retest reliability.

  14. Standard setting: comparison of two methods.

    Science.gov (United States)

    George, Sanju; Haque, M Sayeed; Oyebode, Femi

    2006-09-14

    The outcome of assessments is determined by the standard-setting method used. There is a wide range of standard-setting methods and the two used most extensively in undergraduate medical education in the UK are the norm-reference and the criterion-reference methods. The aims of the study were to compare these two standard-setting methods for a multiple-choice question examination and to estimate the test-retest and inter-rater reliability of the modified Angoff method. The norm-reference method of standard-setting (mean minus 1 SD) was applied to the 'raw' scores of 78 4th-year medical students on a multiple-choice examination (MCQ). Two panels of raters also set the standard using the modified Angoff method for the same multiple-choice question paper on two occasions (6 months apart). We compared the pass/fail rates derived from the norm reference and the Angoff methods and also assessed the test-retest and inter-rater reliability of the modified Angoff method. The pass rate with the norm-reference method was 85% (66/78) and that by the Angoff method was 100% (78 out of 78). The percentage agreement between Angoff method and norm-reference was 78% (95% CI 69% - 87%). The modified Angoff method had an inter-rater reliability of 0.81-0.82 and a test-retest reliability of 0.59-0.74. There were significant differences in the outcomes of these two standard-setting methods, as shown by the difference in the proportion of candidates that passed and failed the assessment. The modified Angoff method was found to have good inter-rater reliability and moderate test-retest reliability.

  15. Neutron activation analysis for certification of standard reference materials

    International Nuclear Information System (INIS)

    Capote Rodriguez, G.; Perez Zayas, G.; Hernandez Rivero, A.; Ribeiro Guevara, S.

    1996-01-01

    Neutron activation analysis is used extensively as one of the analytical techniques in the certification of standard reference materials. Characteristics of neutron activation analysis which make it valuable in this role are: accuracy multielemental capability to asses homogeneity, high sensitivity for many elements, and essentially non-destructive method. This paper report the concentrations of 30 elements (major, minor and trace elements) in four Cuban samples. The samples were irradiated in a thermal neutron flux of 10 12- 10 13 n.cm 2. s -1. The gamma ray spectra were measured by HPGe detectors and were analyzed using ACTAN program development in Center of Applied Studies for Nuclear Development

  16. Certification of standard reference materials employing neutron activation analysis

    International Nuclear Information System (INIS)

    Capote Rodriguez, G.; Hernandez Rivero, A.; Molina Insfran, J.; Ribeiro Guevara, S.; Santana Encinosa, C.; Perez Zayas, G.

    1997-01-01

    Neutron activation analysis (Naa) is used extensively as one of the analytical techniques in the certification of standard reference materials (Srm). Characteristics of Naa which make it valuable in this role are: accuracy; multielemental capability; ability to assess homogeneity; high sensitivity for many elements, and essentially non-destructive method. This paper reports the concentrations of thirty elements (major, minor and trace elements) in four Cuban Srm's. The samples were irradiated in a thermal neutron flux of 10 12 -10 13 neutrons.cm -2 .s -1 . The gamma-ray spectra were measured by HPGe detectors and were analysed using ACTAN program, developed in CEADEN. (author) [es

  17. Japanese tea leaves: a possible biological standard reference material

    International Nuclear Information System (INIS)

    Fuwa, Keiichiro; Notsu, Kenji; Tsunoda, Kin-ichi; Kato, Hideaki; Yamamoto, Yuko.

    1978-01-01

    Japanese Tea Leaves, prepared by pulverizing with an agate ball mill and sieving with a Saran fiber sieve (50 mesh) were assessed as a possible biological standard reference material for elemental analysis. The metal content of the tea leaves was determined independently at two laboratories using atomic absorption and flame emission spectrometry. Neutron activation analysis was also performed to determine the content (21 elements) of Tea Leaves. For some elements the result from the various methods were compared. The characteristics of Tea Leaves are discussed and the elemental composition is compared to that of Orchard Leaves (NBS SRM, 1571). The most significant characteristic of Tea Leaves was the high manganese content. (auth.)

  18. Nuclear microprobe analysis of the standard reference materials

    International Nuclear Information System (INIS)

    Jaksic, M.; Fazinic, S.; Bogdanovic, I.; Tadic, T.

    2002-01-01

    Most of the presently existing Standard Reference Materials (SRM) for nuclear analytical methods are certified for the analyzed mass of the order of few hundred mg. Typical mass of sample which is analyzed by PIXE or XRF methods is very often below 1 mg. By the development of focused proton or x-ray beams, masses which can be typically analyzed go down to μg or even ng level. It is difficult to make biological or environmental SRMs which can give desired homogeneity at such low scale. However, use of fundamental parameter quantitative evaluation procedures (absolute method), minimize needs for SRMs. In PIXE and micro PIXE setup at our Institute, fundamental parameter approach is used. For exact calibration of the quantitative analysis procedure just one standard sample is needed. In our case glass standards which showed homogeneity down to micron scale were used. Of course, it is desirable to use SRMs for quality assurance, and therefore need for homogenous materials can be justified even for micro PIXE method. In this presentation, brief overview of PIXE setup calibration is given, along with some recent results of tests of several SRMs

  19. Hg0 and HgCl2 Reference Gas Standards: NIST Traceability and Comparability (And EPA ALT Methods for Hg and HCl )

    Science.gov (United States)

    EPA and NIST have collaborated to establish the necessary procedures for establishing the required NIST traceability of commercially-provided Hg0 and HgCl2 reference generators. This presentation will discuss the approach of a joint EPA/NIST study to accurately quantify the tru...

  20. Physical fitness reference standards in European children: the IDEFICS study.

    Science.gov (United States)

    De Miguel-Etayo, P; Gracia-Marco, L; Ortega, F B; Intemann, T; Foraita, R; Lissner, L; Oja, L; Barba, G; Michels, N; Tornaritis, M; Molnár, D; Pitsiladis, Y; Ahrens, W; Moreno, L A

    2014-09-01

    A low fitness status during childhood and adolescence is associated with important health-related outcomes, such as increased future risk for obesity and cardiovascular diseases, impaired skeletal health, reduced quality of life and poor mental health. Fitness reference values for adolescents from different countries have been published, but there is a scarcity of reference values for pre-pubertal children in Europe, using harmonised measures of fitness in the literature. The IDEFICS study offers a good opportunity to establish normative values of a large set of fitness components from eight European countries using common and well-standardised methods in a large sample of children. Therefore, the aim of this study is to report sex- and age-specific fitness reference standards in European children. Children (10,302) aged 6-10.9 years (50.7% girls) were examined. The test battery included: the flamingo balance test, back-saver sit-and-reach test (flexibility), handgrip strength test, standing long jump test (lower-limb explosive strength) and 40-m sprint test (speed). Moreover, cardiorespiratory fitness was assessed by a 20-m shuttle run test. Percentile curves for the 1st, 3rd, 10th, 25th, 50th, 75th, 90th, 97th and 99th percentiles were calculated using the General Additive Model for Location Scale and Shape (GAMLSS). Our results show that boys performed better than girls in speed, lower- and upper-limb strength and cardiorespiratory fitness, and girls performed better in balance and flexibility. Older children performed better than younger children, except for cardiorespiratory fitness in boys and flexibility in girls. Our results provide for the first time sex- and age-specific physical fitness reference standards in European children aged 6-10.9 years.

  1. Evaluation methods for neutron cross section standards

    International Nuclear Information System (INIS)

    Bhat, M.R.

    1980-01-01

    Methods used to evaluate the neutron cross section standards are reviewed and their relative merits, assessed. These include phase-shift analysis, R-matrix fit, and a number of other methods by Poenitz, Bhat, Kon'shin and the Bayesian or generalized least-squares procedures. The problems involved in adopting these methods for future cross section standards evaluations are considered, and the prospects for their use, discussed. 115 references, 5 figures, 3 tables

  2. Standardized waste form test methods

    International Nuclear Information System (INIS)

    Slate, S.C.

    1984-01-01

    The Materials Characterization Center (MCC) is developing standard tests to characterize nuclear waste forms. Development of the first thirteen tests was originally initiated to provide data to compare different high-level waste (HLW) forms and to characterize their basic performance. The current status of the first thirteen MCC tests and some sample test results are presented: the radiation stability tests (MCC-6 and 12) and the tensile-strength test (MCC-11) are approved; the static leach tests (MCC-1, 2, and 3) are being reviewed for full approval; the thermal stability (MCC-7) and microstructure evaluation (MCC-13) methods are being considered for the first time; and the flowing leach test methods (MCC-4 and 5), the gas generation methods (MCC-8 and 9), and the brittle fracture method (MCC-10) are indefinitely delayed. Sample static leach test data on the ARM-1 approved reference material are presented. Established tests and proposed new tests will be used to meet new testing needs. For waste form production, tests on stability and composition measurement are needed to provide data to ensure waste form quality. In transporation, data are needed to evaluate the effects of accidents on canisterized waste forms. The new MCC-15 accident test method and some data are presented. Compliance testing needs required by the recent draft repository waste acceptance specifications are described. These specifications will control waste form contents, processing, and performance

  3. [Application of traditional Chinese medicine reference standards in quality control of Chinese herbal pieces].

    Science.gov (United States)

    Lu, Tu-Lin; Li, Jin-Ci; Yu, Jiang-Yong; Cai, Bao-Chang; Mao, Chun-Qin; Yin, Fang-Zhou

    2014-01-01

    Traditional Chinese medicine (TCM) reference standards plays an important role in the quality control of Chinese herbal pieces. This paper overviewed the development of TCM reference standards. By analyzing the 2010 edition of Chinese pharmacopoeia, the application of TCM reference standards in the quality control of Chinese herbal pieces was summarized, and the problems exiting in the system were put forward. In the process of improving the quality control level of Chinese herbal pieces, various kinds of advanced methods and technology should be used to research the characteristic reference standards of Chinese herbal pieces, more and more reasonable reference standards should be introduced in the quality control system of Chinese herbal pieces. This article discussed the solutions in the aspect of TCM reference standards, and future development of quality control on Chinese herbal pieces is prospected.

  4. Semi-automatic construction of reference standards for evaluation of image registration

    NARCIS (Netherlands)

    Murphy, K.; Ginneken, van B.; Klein, S.; Staring, M.; Hoop, de B.J.; Viergever, M.A.; Pluim, J.P.W.

    2011-01-01

    Quantitative evaluation of image registration algorithms is a difficult and under-addressed issue due to the lack of a reference standard in most registration problems. In this work a method is presented whereby detailed reference standard data may be constructed in an efficient semi-automatic

  5. Hepatic fat quantification: a prospective comparison of magnetic resonance spectroscopy and analysis methods for chemical-shift gradient echo magnetic resonance imaging with histologic assessment as the reference standard.

    Science.gov (United States)

    Kang, Bo-Kyeong; Yu, Eun Sil; Lee, Seung Soo; Lee, Youngjoo; Kim, Namkug; Sirlin, Claude B; Cho, Eun Yoon; Yeom, Suk Keu; Byun, Jae Ho; Park, Seong Ho; Lee, Moon-Gyu

    2012-06-01

    The aims of this study were to assess the confounding effects of hepatic iron deposition, inflammation, and fibrosis on hepatic steatosis (HS) evaluation by magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) and to assess the accuracies of MRI and MRS for HS evaluation, using histology as the reference standard. In this institutional review board-approved prospective study, 56 patients gave informed consents and underwent chemical-shift MRI and MRS of the liver on a 1.5-T magnetic resonance scanner. To estimate MRI fat fraction (FF), 4 analysis methods were used (dual-echo, triple-echo, multiecho, and multi-interference), and MRS FF was calculated with T2 correction. Degrees of HS, iron deposition, inflammation, and fibrosis were analyzed in liver resection (n = 37) and biopsy (n = 19) specimens. The confounding effects of histology on fat quantification were assessed by multiple linear regression analysis. Using the histologic degree of HS as the reference standard, the accuracies of each method in estimating HS and diagnosing an HS of 5% or greater were determined by linear regression and receiver operating characteristic analyses. Iron deposition significantly confounded estimations of FF by the dual-echo (P hepatic fat, with coexisting histologic abnormalities having no confounding effects.

  6. Bibliographic Citations With Special Reference Indian Bibliographic Standard

    Directory of Open Access Journals (Sweden)

    Reshmi Sarkar

    2015-08-01

    Full Text Available Bibliographic citation is playing an important role today to ensure the completeness of all research activities. They occupy an integral part as a reference in all types of resources need. The author while writing a paper takes the references from a number of documents and finally quotes them with its bibliographic details to recognize the work of earlier authors in the same field of study. With the virtually exponential growth in the research literatures throughout the 20th century it has become clear that the larger the literature the more difficult are the problems caused by poorly crafted bibliographic references. Scholarly societies like publishers of research journals have either produced their own or have endorsed common bibliographic style manuals or standards. In this study we have studied several style manuals and standards for bibliographic referencing and several editorial guidelines for this purpose to compare them. Indian bibliographic standard gets special attention.

  7. On criteria for examining analysis quality with standard reference material

    International Nuclear Information System (INIS)

    Yang Huating

    1997-01-01

    The advantages and disadvantages and applicability of some criteria for examining analysis quality with standard reference material are discussed. The combination of the uncertainties of the instrument examined and the reference material should be determined on the basis of specific situations. Without the data of the instrument's uncertainty, it would be applicable to substitute the standard deviation multiplied by certain times for the uncertainty. The result of the examining should not result in more error reported in routine measurements than it really is. Over strict examining should also be avoided

  8. Standard digital reference images for inspection of aluminum castings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 These digital reference images illustrate the types and degrees of discontinuities that may be found in aluminum-alloy castings. The castings illustrated are in thicknesses of 1/ 4 in. [6.35 mm] and 3/4 in. [19.1mm]. 1.2 All areas of this standard may be open to agreement between the cognizant engineering organization and the supplier, or specific direction from the cognizant engineering organization. These items should be addressed in the purchase order or the contract. 1.3 The values stated in inch-pound units are to be regarded as standard. 1.4 These digital reference images are not intended to illustrate the types and degrees of discontinuities found in aluminum-alloy castings when performing film radiography. If performing film radiography of aluminum-alloy castings, refer to Reference Radiographs E 155. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and he...

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

    Science.gov (United States)

    Sharpless, K E; Gill, L M

    2000-01-01

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

  10. Dehydroepiandrosterone sulfate quantification in serum using high-performance liquid chromatography/mass spectrometry and a deuterated internal standard: a technique suitable for routine use or as a reference method

    International Nuclear Information System (INIS)

    Shackleton, C.H.; Kletke, C.; Wudy, S.; Pratt, J.H.

    1990-01-01

    A thermospray high-performance liquid chromatography/mass spectrometry method for determination of serum dehydroepiandrosterone sulfate is described. The steroid was measured intact using [7,7-2H2]dehydroepiandrosterone sulfate as internal standard. The analysis was carried out in the negative ion mode by determining the peak height ratio of the molecular anions of the analyte and internal standard. The method was used to determine the steroid in serum from 15 male and female normal adults and the following values were obtained: males, 272 +/- 45 micrograms/dl (range, 197 to 331 micrograms/dl) and females, 215 +/- 67 micrograms/dl (range, 107 to 347 micrograms/dl). In addition, dehydroepiandrosterone sulfate was measured by high-performance liquid chromatography/mass spectrometry and radioimmunoassay (a commercial kit) on 25 individuals of all age groups. There was strong correlation between the values obtained, but the radioimmunoassay values were generally double those obtained by high-performance liquid chromatography/mass spectrometry. Three other steroid sulfates, androsterone sulfate, epiandrosterone sulfate, and androst-5-ene-3 beta, 17 beta-diol sulfate, were also assayed. In males, these had mean values of 112, 44, and 13 micrograms/dl and, in females, they had mean values of 84, 25, and 6 micrograms/dl, respectively. Radioimmunoassay cross-reactivity measurement for these steroids (as reference compounds) showed that they were unlikely to contribute greatly to the discrepancy between radioimmunoassay and high-performance liquid chromatography/mass spectrometry values

  11. Reference standard for serum bile acids in pregnancy.

    LENUS (Irish Health Repository)

    2012-01-31

    Please cite this paper as: Egan N, Bartels A, Khashan A, Broadhurst D, Joyce C, O\\'Mullane J, O\\'Donoghue K. Reference standard for serum bile acids in pregnancy. BJOG 2012;00:000-000. DOI: 10.1111\\/j.1471-0528.2011.03245.x. Objective Obstetric cholestasis (OC) is a liver disorder characterised by pruritus and elevated serum bile acids (SBA) that affects one in 200 pregnant women. It is associated with adverse perinatal outcomes such as premature delivery and stillbirth. Mild OC is defined as SBA levels of 10-39 mumol\\/l, and severe OC is defined by levels >40 mumol\\/l. SBA levels in normal pregnancy have not been investigated. We aimed to establish reference values for SBA in healthy pregnant women across different trimesters of pregnancy. Design Cross-sectional analysis of SBA levels. Setting A large tertiary referral university teaching maternity hospital. Population Healthy pregnant women with a singleton pregnancy and a body mass index (BMI) < 40, excluding women with significant alcohol intake, history of liver disease, prior cholecystectomy and OC. Methods Cross-sectional analysis of SBA levels at 12, 20, 28 and 36 weeks of gestation, and on days 1-3 postpartum. Main outcome measures SBA levels in mumol\\/l. Results A total of 219 women attending for antenatal care were recruited, and SBA levels were assayed at 12, 20, 28 and 36 weeks of gestation, and up to 72 hours postpartum (n = 44-49 cases at each stage). The majority were white European women, with a median age of 30 years (range 17-46 years) and median BMI of 25 (range 18-38). Values of SBA ranged from 0.3 to 9.8 mumol\\/l in 216 women, with only three measurements outside this range. There were no significant changes throughout pregnancy. Conclusions SBA values in uncomplicated pregnancies are consistent, regardless of gestation, and are not elevated in pregnancy. The current reference values for the diagnosis of OC appear to be appropriate.

  12. Improving the efficiency of quantitative (1)H NMR: an innovative external standard-internal reference approach.

    Science.gov (United States)

    Huang, Yande; Su, Bao-Ning; Ye, Qingmei; Palaniswamy, Venkatapuram A; Bolgar, Mark S; Raglione, Thomas V

    2014-01-01

    The classical internal standard quantitative NMR (qNMR) method determines the purity of an analyte by the determination of a solution containing the analyte and a standard. Therefore, the standard must meet the requirements of chemical compatibility and lack of resonance interference with the analyte as well as a known purity. The identification of such a standard can be time consuming and must be repeated for each analyte. In contrast, the external standard qNMR method utilizes a standard with a known purity to calibrate the NMR instrument. The external standard and the analyte are measured separately, thereby eliminating the matter of chemical compatibility and resonance interference between the standard and the analyte. However, the instrumental factors, including the quality of NMR tubes, must be kept the same. Any deviations will compromise the accuracy of the results. An innovative qNMR method reported herein utilizes an internal reference substance along with an external standard to assume the role of the standard used in the traditional internal standard qNMR method. In this new method, the internal reference substance must only be chemically compatible and be free of resonance-interference with the analyte or external standard whereas the external standard must only be of a known purity. The exact purity or concentration of the internal reference substance is not required as long as the same quantity is added to the external standard and the analyte. The new method reduces the burden of searching for an appropriate standard for each analyte significantly. Therefore the efficiency of the qNMR purity assay increases while the precision of the internal standard method is retained. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. A routine chromium determination in biological materials; application to various reference materials and standard reference materials

    International Nuclear Information System (INIS)

    Tjioe, P.S.; Goeij, J.J.M. de; Volkers, K.J.

    1979-01-01

    The determination limit under standard working conditions of chromium in biological materials is discussed. Neutron activation analysis and atomic spectrometry have been described for some analytical experiences with NBS SRM 1577 reference material. The chromium determination is a part of a larger multi-element scheme for the determination of 12 elements in biological materials

  14. Consensus values for NIST biological and environmental Standard Reference Materials

    International Nuclear Information System (INIS)

    Roelandts, I.; Gladney, E.S.

    1998-01-01

    The National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards or NBS) has produced numerous Standard Reference Materials (SRM) for use in biological and environmental analytical chemistry. The value listed on the ''NIST Certificate of Analysis'' is the present best estimate of the ''true'' concentration of that element and is not expected to deviate from that concentration by more than the stated uncertainty. However, NIST does not certify the elemental concentration of every constituent and the number of elements reported in the NIST programs tends to be limited.Numerous analysts have published concentration data on these reference materials. Major journals in analytical chemistry, books, proceedings and ''technical reports'' have been surveyed to collect these available literature values. A standard statistical approach has been employed to evaluate the compiled data. Our methodology has been developed in a series of previous papers. Some subjective criteria are first used to reject aberrant data. Following these eliminations, an initial arithmetic mean and standard deviation (S.D.) are computed from remaining data for each element. All data now outside two S.D. from the initial mean are dropped and a second mean and S.D. recalculated. These final means and associated S.D. are reported as ''consensus values'' in our tables. (orig.)

  15. Positive animal welfare states and reference standards for welfare assessment.

    Science.gov (United States)

    Mellor, D J

    2015-01-01

    Developments in affective neuroscience and behavioural science during the last 10-15 years have together made it increasingly apparent that sentient animals are potentially much more sensitive to their environmental and social circumstances than was previously thought to be the case. It therefore seems likely that both the range and magnitude of welfare trade-offs that occur when animals are managed for human purposes have been underestimated even when minimalistic but arguably well-intentioned attempts have been made to maintain high levels of welfare. In light of these neuroscience-supported behaviour-based insights, the present review considers the extent to which the use of currently available reference standards might draw attention to these previously neglected areas of concern. It is concluded that the natural living orientation cannot provide an all-embracing or definitive welfare benchmark because of its primary focus on behavioural freedom. However assessments of this type, supported by neuroscience insights into behavioural motivation, may now carry greater weight when used to identify management practices that should be avoided, discontinued or substantially modified. Using currently accepted baseline standards as welfare reference points may result in small changes being accorded greater significance than would be the case if they were compared with higher standards, and this could slow the progress towards better levels of welfare. On the other hand, using "what animals want" as a reference standard has the appeal of focusing on the specific resources or conditions the animals would choose themselves and can potentially improve their welfare more quickly than the approach of making small increments above baseline standards. It is concluded that the cautious use of these approaches in different combinations could lead to recommendations that would more effectively promote positive welfare states in hitherto neglected areas of concern.

  16. 78 FR 21850 - Federal Motor Vehicle Safety Standards; Matters Incorporated by Reference

    Science.gov (United States)

    2013-04-12

    ... to the 1985 Annual Book of ASTM Standards, Vol. 05.04, ``Test Methods for Rating Motor, Diesel... for Rating Motor, Diesel, Aviation Fuels, A2. Reference Materials and Blending Accessories, (``ASTM... [Docket No. NHTSA-2011-0185] RIN 2127-AL25 Federal Motor Vehicle Safety Standards; Matters Incorporated by...

  17. Characterization of reference standards for dirt by Laser Ablation Induced Photoacoustics (LAIP)

    International Nuclear Information System (INIS)

    Orzi, D J O; Bilmes, G M; Morel, E N; Torga, J R; Roviglione, A N

    2010-01-01

    Measurements of surface cleanliness and dirt characterization are important problems in a wide range of processes in industry and production. Standard methods are in most cases cumbersome laboratory procedures that must be performed out of the production lines. Instruments and methods for cleanliness determination and dirt characterization require reference standards for calibration. For that purpose we built a possible dirt reference standard (DRS) made by films of graphite grease subjected to heat treatment for mechanical stabilization. The DRS characterization was performed by Laser Ablation Induced Photoacoustics (LAIP). The measurement of the thickness of the films was made by low-coherence interferometry.

  18. A reference standard-based quality assurance program for radiology.

    Science.gov (United States)

    Liu, Patrick T; Johnson, C Daniel; Miranda, Rafael; Patel, Maitray D; Phillips, Carrie J

    2010-01-01

    The authors have developed a comprehensive radiology quality assurance (QA) program that evaluates radiology interpretations and procedures by comparing them with reference standards. Performance metrics are calculated and then compared with benchmarks or goals on the basis of published multicenter data and meta-analyses. Additional workload for physicians is kept to a minimum by having trained allied health staff members perform the comparisons of radiology reports with the reference standards. The performance metrics tracked by the QA program include the accuracy of CT colonography for detecting polyps, the false-negative rate for mammographic detection of breast cancer, the accuracy of CT angiography detection of coronary artery stenosis, the accuracy of meniscal tear detection on MRI, the accuracy of carotid artery stenosis detection on MR angiography, the accuracy of parathyroid adenoma detection by parathyroid scintigraphy, the success rate for obtaining cortical tissue on ultrasound-guided core biopsies of pelvic renal transplants, and the technical success rate for peripheral arterial angioplasty procedures. In contrast with peer-review programs, this reference standard-based QA program minimizes the possibilities of reviewer bias and erroneous second reviewer interpretations. The more objective assessment of performance afforded by the QA program will provide data that can easily be used for education and management conferences, research projects, and multicenter evaluations. Additionally, such performance data could be used by radiology departments to demonstrate their value over nonradiology competitors to referring clinicians, hospitals, patients, and third-party payers. Copyright 2010 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  19. From plastic to gold: a unified classification scheme for reference standards in medical image processing

    Science.gov (United States)

    Lehmann, Thomas M.

    2002-05-01

    Reliable evaluation of medical image processing is of major importance for routine applications. Nonetheless, evaluation is often omitted or methodically defective when novel approaches or algorithms are introduced. Adopted from medical diagnosis, we define the following criteria to classify reference standards: 1. Reliance, if the generation or capturing of test images for evaluation follows an exactly determined and reproducible protocol. 2. Equivalence, if the image material or relationships considered within an algorithmic reference standard equal real-life data with respect to structure, noise, or other parameters of importance. 3. Independence, if any reference standard relies on a different procedure than that to be evaluated, or on other images or image modalities than that used routinely. This criterion bans the simultaneous use of one image for both, training and test phase. 4. Relevance, if the algorithm to be evaluated is self-reproducible. If random parameters or optimization strategies are applied, reliability of the algorithm must be shown before the reference standard is applied for evaluation. 5. Significance, if the number of reference standard images that are used for evaluation is sufficient large to enable statistically founded analysis. We demand that a true gold standard must satisfy the Criteria 1 to 3. Any standard only satisfying two criteria, i.e., Criterion 1 and Criterion 2 or Criterion 1 and Criterion 3, is referred to as silver standard. Other standards are termed to be from plastic. Before exhaustive evaluation based on gold or silver standards is performed, its relevance must be shown (Criterion 4) and sufficient tests must be carried out to found statistical analysis (Criterion 5). In this paper, examples are given for each class of reference standards.

  20. Measurement of the depth of narrow slotted sections in eddy current reference standards

    Science.gov (United States)

    Kim, Young-Joo; Kim, Young-gil; Ahn, Bongyoung; Yoon, Dong-Jin

    2007-02-01

    The dimensions of the slots in eddy current (EC) reference standards are too narrow to be measured by general depth measurement methods such as the optical (laser) or stylus methods. However, measurement of the dimensions of the machined slots is a prerequisite to using the blocks as references. The present paper suggests a measurement method for the slotted section using an ultrasonic test. The width and depth of the slots measured in our study are roughly 0.1 mm and 0.5 mm, respectively. The time of flight (TOF) of the ultrasonic wave was measured precisely. The ultrasonic velocity in the material of the EC reference standard was calculated with the measured values of the TOF and its thickness. Reflected waves from the tip of the slot and the bottom surface of the EC standard were successfully classified. Using this method we have successfully determined the depth of the slotted section.

  1. Quality of Standard Reference Materials for Short Time Activation Analysis

    International Nuclear Information System (INIS)

    Ismail, S.S.; Oberleitner, W.

    2003-01-01

    Some environmental reference materials (CFA-1633 b, IAEA-SL-1, SARM-1,BCR-176, Coal-1635, IAEA-SL-3, BCR-146, and SRAM-5) were analysed by short-time activation analysis. The results show that these materials can be classified in three groups, according to their activities after irradiation. The obtained results were compared in order to create a quality index for determination of short-lived nuclides at high count rates. It was found that Cfta is not a suitable standard for determining very short-lived nuclides (half-lives<1 min) because the activity it produces is 15-fold higher than that SL-3. Biological reference materials, such as SRM-1571, SRM-1573, SRM-1575, SRM-1577, IAEA-392, and IAEA-393, were also investigated by a higher counting efficiency system. The quality of this system and its well-type detector for investigating short-lived nuclides was discussed

  2. Standard reference materials analysis for MINT Radiocarbon Laboratory

    International Nuclear Information System (INIS)

    Noraishah Othman; Kamisah Alias; Nasasni Nasrul

    2004-01-01

    As a follow-up to the setting up of the MINT Radiocarbon Dating facility. an exercise on the IAEA standard reference materials was carried out. Radiocarbon laboratories frequently used these 8 natural samples to verify their systems. The materials were either pretreated or analysed directly to determine the activity of 14 C isotopes of the five samples expressed in % Modern (pMC) terms and to make recommendations on further use of these materials. We present the results of the five materials and discuss the analyses that were undertaken. (Author)

  3. The Quality Control of Reference Standards in Metrology Dosimetry

    International Nuclear Information System (INIS)

    Lazarevic, Dj.; Ciraj Bjelac, O.; Kovacevic, M.; Vukcevic, M.

    2008-01-01

    This works presents the quality control tests applied to two types of ionization chambers with suitable electrometers. Measuring assemblies were tested in order to assess their performance and adequacy for use as reference standards in ionising radiation metrology laboratory for calibrations in the field of radiotherapy and radiation protection. Two types of ionizing chambers (Farmer type, 0.6 cm 3 and spherical ionizing chamber, 1 l) with suitable electrometers were tested. Following test were performed: repeatability, long term stability, polarity and leakage current measurement. All tested measuring assemblies demonstrated proper performance, correctness and high reliance of measurements, since all implemented quality control test results were within acceptable limits. (author)

  4. Development of the NBS beryllium isotopic standard reference material

    International Nuclear Information System (INIS)

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

    1987-01-01

    The National Bureau of Standards, in conjunction with the Oak Ridge National Laboratory and the Accelerator Mass Spectrometry community, is in the process of developing a beryllium isotopic solution Standard Reference Material. The master 10 Be/ 9 Be solution was characterized isotopically by resonance-ionization and secondary-ion mass-spectrometric-based techniques, and radioactivity measurements were by liquid scintillation counting. The master solution was gravimetrically diluted with 9 Be to a final 10 Be/ 9 Be atomic ratio of 3 x 10 -11 . The preliminary data indicate a half life for 10 Be of 1.3 million years, and AMS measurements are within 10% of the known beryllium isotopic ratio

  5. New Carbonate Standard Reference Materials for Boron Isotope Geochemistry

    Science.gov (United States)

    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

  6. Determination of sampling constants in NBS geochemical standard reference materials

    International Nuclear Information System (INIS)

    Filby, R.H.; Bragg, A.E.; Grimm, C.A.

    1986-01-01

    Recently Filby et al. showed that, for several elements, National Bureau of Standards (NBS) Fly Ash standard reference material (SRM) 1633a was a suitable reference material for microanalysis (sample weights 2 , and the mean sample weight, W vector, K/sub s/ = (S/sub s/%) 2 W vector, could not be determined from these data because it was not possible to quantitate other sources of error in the experimental variances. K/sub s/ values for certified elements in geochemical SRMs provide important homogeneity information for microanalysis. For mineralogically homogeneous SRMs (i.e., small K/sub s/ values for associated elements) such as the proposed clays, it is necessary to determine K/sub s/ by analysis of very small sample aliquots to maximize the subsampling variance relative to other sources of error. This source of error and the blank correction for the sample container can be eliminated by determining K/sub s/ from radionuclide activities of weighed subsamples of a preirradiated SRM

  7. Hg0 and HgCl2 Reference Gas Standards: ?NIST Traceability ...

    Science.gov (United States)

    EPA and NIST have collaborated to establish the necessary procedures for establishing the required NIST traceability of commercially-provided Hg0 and HgCl2 reference generators. This presentation will discuss the approach of a joint EPA/NIST study to accurately quantify the true concentrations of Hg0 and HgCl2 reference gases produced from high quality, NIST-traceable, commercial Hg0 and HgCl2 generators. This presentation will also discuss the availability of HCl and Hg0 compressed reference gas standards as a result of EPA's recently approved Alternative Methods 114 and 118. Gaseous elemental mercury (Hg0) and oxidized mercury (HgCl2) reference standards are integral to the use of mercury continuous emissions monitoring systems (Hg CEMS) for regulatory compliance emissions monitoring. However, a quantitative disparity of approximately 7-10% has been observed between commercial Hg0 and HgCl2 reference gases which currently limits the use of (HgCl2) reference gas standards. Resolving this disparity would enable the expanded use of (HgCl2) reference gas standards for regulatory compliance purposes.

  8. International Longitudinal Paediatric Reference Standards for Bone Mineral Content

    Science.gov (United States)

    Baxter-Jones, Adam DG; McKay, Heather; Burrows, Melonie; Bachrach, Laura K; Lloyd, Tom; Petit, Moira; Macdonald, Heather; Mirwald, Robert L; Bailey, Don

    2014-01-01

    To render a diagnosis pediatricians rely upon reference standards for bone mineral density or bone mineral content, which are based on cross-sectional data from a relatively small sample of children. These standards are unable to adequately represent growth in a diverse pediatric population. Thus, the goal of this study was to develop sex and site specific standards for BMC using longitudinal data collected from four international sites in Canada and the United States. Data from four studies were combined; Saskatchewan Paediatric Bone Mineral Accrual Study (n=251), UBC Healthy Bones Study (n=382); Penn State Young Women’s Health Study (n=112) and Stanford’s Bone Mineral Accretion study (n=423). Males and females (8 to 25 years) were measured for whole body (WB), total proximal femur (PF), femoral neck (FN) and lumbar spine (LS) BMC (g). Data were analyzed using random effects models. Bland-Altman was used to investigate agreement in predicted and actual data. Age, height, weight and ethnicity independently predicted BMC accrual across sites (P accrual; Hispanic 75.4 (28.2) g less BMC accrual; Blacks 82.8 (26.3) g more BMC accrual with confounders of age, height and weight controlled. Similar findings were found for PF and FN. Female models for all sites were similar with age, height and weight all independent significant predictors of BMC accrual (P accounting for age, size, sex and ethnicity. In conclusion, when interpreting BMC in paediatrics we recommend standards that are sex, age, size and ethnic specific. PMID:19854308

  9. International longitudinal pediatric reference standards for bone mineral content.

    Science.gov (United States)

    Baxter-Jones, Adam D G; Burrows, Melonie; Bachrach, Laura K; Lloyd, Tom; Petit, Moira; Macdonald, Heather; Mirwald, Robert L; Bailey, Don; McKay, Heather

    2010-01-01

    To render a diagnosis pediatricians rely upon reference standards for bone mineral density or bone mineral content, which are based on cross-sectional data from a relatively small sample of children. These standards are unable to adequately represent growth in a diverse pediatric population. Thus, the goal of this study was to develop sex and site-specific standards for BMC using longitudinal data collected from four international sites in Canada and the United States. Data from four studies were combined; Saskatchewan Paediatric Bone Mineral Accrual Study (n=251), UBC Healthy Bones Study (n=382); Penn State Young Women's Health Study (n=112) and Stanford's Bone Mineral Accretion study (n=423). Males and females (8 to 25 years) were measured for whole body (WB), total proximal femur (PF), femoral neck (FN) and lumbar spine (LS) BMC (g). Data were analyzed using random effects models. Bland-Altman was used to investigate agreement between predicted and actual data. Age, height, weight and ethnicity independently predicted BMC accrual across sites (Paccrual; Hispanic 75.4 (28.2) g less BMC accrual; Blacks 82.8 (26.3) g more BMC accrual with confounders of age, height and weight controlled. We report similar findings for the PF and FN. Models for females for all sites were similar with age, height and weight as independent significant predictors of BMC accrual (Paccounting for age, size, sex and ethnicity. In conclusion, when interpreting BMC in pediatrics we recommend standards that are sex, age, size and ethnic specific. Copyright (c) 2009 Elsevier Inc. All rights reserved.

  10. Einmaliges studentisches standardisiertes Training der chirurgischen Händedesinfektion nach EN1500: Quantifizierung des Trainingseffektes, Nutzen der Methode und Vergleich mit klinischen Referenzgruppen [A single standardized practical training for surgical scrubbing according to EN1500: Effect Quantification, value of the standardized method and comparison with clinical reference groups

    Directory of Open Access Journals (Sweden)

    Wullenk, Katharina

    2013-05-01

    Full Text Available [english] The standardized training of practical competences in skills labs is relatively new among German Medical Faculties. The broad acceptance and outstanding evaluation results do not provide objective data on the efficiency and cost-efficiency of these trainings. This study aims on the quantification of the teaching effect of the surgical scrubbing technique EN1500 and its comparison with clinical references of OR personnel.Methods: 161 4 year medical students were randomized into intervention and control group. The intervention group received a 45 minute standardized peer-teaching training of practical competences necessary in the OR including the scrubbing according to EN1500. Fluorescence dye was mixed in the disinfectant solution. After hand disinfection, standardized fotographs and semi-automated digital processing resulted in quantification of the insufficiently covered hand area. These results were compared with the control group that received the training after the test. In order to provide information on the achieved clinical competence level, the results were compared with the two clinical reference groups.Results: The intervention group remained with 4,99% (SD 2,34 insufficiently covered hand area after the training compared to the control group 7,33% (SD 3,91, p[german] Die standardisierte Schulung klinisch-praktischer Fertigkeiten in sog. Skills Labs ist erst seit wenigen Jahren an deutschen Universitäten verbreitet. Den zumeist umfangreichen und sehr guten Evaluationsergebnissen stehen kaum Untersuchungen zur Effektquantifizierung und Kosten-Nutzen-Analyse gegenüber. In der vorliegenden Studie soll eine Methode zur digitalen Quantifizierung der Güte der chirurgischen Händedesinfektion vorgestellt werden sowie das Skills-Lab-Training der standardisierten Einreibemethode nach EN1500 auf seinen Effekt hin untersucht und mit OP-Pflegepersonal und Operateuren als klinische Referenzgruppen verglichen werden.Methode: 161

  11. Universal Reference RNA as a standard for microarray experiments

    Directory of Open Access Journals (Sweden)

    Fero Michael

    2004-03-01

    Full Text Available Abstract Background Obtaining reliable and reproducible two-color microarray gene expression data is critically important for understanding the biological significance of perturbations made on a cellular system. Microarray design, RNA preparation and labeling, hybridization conditions and data acquisition and analysis are variables difficult to simultaneously control. A useful tool for monitoring and controlling intra- and inter-experimental variation is Universal Reference RNA (URR, developed with the goal of providing hybridization signal at each microarray probe location (spot. Measuring signal at each spot as the ratio of experimental RNA to reference RNA targets, rather than relying on absolute signal intensity, decreases variability by normalizing signal output in any two-color hybridization experiment. Results Human, mouse and rat URR (UHRR, UMRR and URRR, respectively were prepared from pools of RNA derived from individual cell lines representing different tissues. A variety of microarrays were used to determine percentage of spots hybridizing with URR and producing signal above a user defined threshold (microarray coverage. Microarray coverage was consistently greater than 80% for all arrays tested. We confirmed that individual cell lines contribute their own unique set of genes to URR, arguing for a pool of RNA from several cell lines as a better configuration for URR as opposed to a single cell line source for URR. Microarray coverage comparing two separately prepared batches each of UHRR, UMRR and URRR were highly correlated (Pearson's correlation coefficients of 0.97. Conclusion Results of this study demonstrate that large quantities of pooled RNA from individual cell lines are reproducibly prepared and possess diverse gene representation. This type of reference provides a standard for reducing variation in microarray experiments and allows more reliable comparison of gene expression data within and between experiments and

  12. Initial testing of a neutron activation analysis system by analysing standard reference materials

    International Nuclear Information System (INIS)

    Suhaimi Hamzah; Roslan Idris; Abdul Khalik Haji Wood; Che Seman Mahmood; Abdul Rahim Mohamad Noor.

    1983-01-01

    This paper describes the data acquisition and processing system in our laboratories (ND6600), the methods of activation analysis and the results obtained from our analysis of IAEA standard reference material (SL-l lake sediments and NBS coal ash 1632a). These standards were analysed in order to check the capability of the system, which was designed in such a way as to enable the user to independently collect and process data from multiple radiation detectors. (author)

  13. 76 FR 8989 - Federal Acquisition Regulation; Updated Financial Accounting Standards Board Accounting References

    Science.gov (United States)

    2011-02-16

    ... Acquisition Regulation; Updated Financial Accounting Standards Board Accounting References AGENCIES... Acquisition Regulation (FAR) to update references to authoritative accounting standards owing to the Financial... Accounting Principles (GAAP) (``Codification of GAAP''). DATES: Interested parties should submit written...

  14. Measurement standards and the general problem of reference points in chemical analysis

    International Nuclear Information System (INIS)

    Richter, W.; Dube, G.

    2002-01-01

    Besides the measurement standards available in general metrology in the form of the realisations of the units of measurement, measurement standards of chemical composition are needed for the vast field of chemical measurement (measurements of the chemical composition), because it is the main aim of such measurements to quantify non-isolated substances, often in complicated matrices, to which the 'classical' measurement standards and their lower- level derivatives are not directly applicable. At present, material artefacts as well as standard measurement devices serve as chemical measurement standards. These are measurement standards in the full metrological sense only, however, if they are firmly linked to the SI unit in which the composition represented by the standard is expressed. This requirement has the consequence that only a very restricted number of really reliable chemical measurement standards exist at present. Since it is very difficult and time consuming to increase this number substantially and, on the other hand, reliable reference points are increasingly needed for all kinds of chemical measurements, primary methods of measurement and high-level reference measurements will play an increasingly important role for the establishment of worldwide comparability and hence mutual acceptance of chemical measurement results. (author)

  15. New reference charts for testicular volume in Dutch children and adolescents allow the calculation of standard deviation scores

    NARCIS (Netherlands)

    Joustra, S.D.; Plas, E.M. van der; Goede, J.; Oostdijk, W.; Delemarre-van de Waal, H.A.; Hack, W.W.M.; Buuren, S. van; Wit, J.M.

    2015-01-01

    Aim Accurate calculations of testicular volume standard deviation (SD) scores are not currently available. We constructed LMS-smoothed age-reference charts for testicular volume in healthy boys. Methods The LMS method was used to calculate reference data, based on testicular volumes from

  16. 40 CFR 53.16 - Supersession of reference methods.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Supersession of reference methods. 53... (CONTINUED) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS General Provisions § 53.16 Supersession of reference methods. (a) This section prescribes procedures and criteria applicable to requests that...

  17. Simultaneous Determination of Four Anthraquinones in Polygoni Multiflori Radix with Single Reference Standard by High Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Hua Yang

    2015-07-01

    Full Text Available Objective: To establish a rapid, accurate and reliable analytical method for the simultaneous determination of four major anthraquinones in Polygoni Multiflori Radix (PMR using single reference standard.

  18. A Framework for Establishing Standard Reference Scale of Texture by Multivariate Statistical Analysis Based on Instrumental Measurement and Sensory Evaluation.

    Science.gov (United States)

    Zhi, Ruicong; Zhao, Lei; Xie, Nan; Wang, Houyin; Shi, Bolin; Shi, Jingye

    2016-01-13

    A framework of establishing standard reference scale (texture) is proposed by multivariate statistical analysis according to instrumental measurement and sensory evaluation. Multivariate statistical analysis is conducted to rapidly select typical reference samples with characteristics of universality, representativeness, stability, substitutability, and traceability. The reasonableness of the framework method is verified by establishing standard reference scale of texture attribute (hardness) with Chinese well-known food. More than 100 food products in 16 categories were tested using instrumental measurement (TPA test), and the result was analyzed with clustering analysis, principal component analysis, relative standard deviation, and analysis of variance. As a result, nine kinds of foods were determined to construct the hardness standard reference scale. The results indicate that the regression coefficient between the estimated sensory value and the instrumentally measured value is significant (R(2) = 0.9765), which fits well with Stevens's theory. The research provides reliable a theoretical basis and practical guide for quantitative standard reference scale establishment on food texture characteristics.

  19. Standard methods for sampling North American freshwater fishes

    Science.gov (United States)

    Bonar, Scott A.; Hubert, Wayne A.; Willis, David W.

    2009-01-01

    This important reference book provides standard sampling methods recommended by the American Fisheries Society for assessing and monitoring freshwater fish populations in North America. Methods apply to ponds, reservoirs, natural lakes, and streams and rivers containing cold and warmwater fishes. Range-wide and eco-regional averages for indices of abundance, population structure, and condition for individual species are supplied to facilitate comparisons of standard data among populations. Provides information on converting nonstandard to standard data, statistical and database procedures for analyzing and storing standard data, and methods to prevent transfer of invasive species while sampling.

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

    DEFF Research Database (Denmark)

    Creech, John Benjamin; Baker, J. A.; Handler, M. R.

    2014-01-01

    . 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...... 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...

  1. Validity and Reliability of a Glucometer Against Industry Reference Standards.

    Science.gov (United States)

    Salacinski, Amanda J; Alford, Micah; Drevets, Kathryn; Hart, Sarah; Hunt, Brian E

    2014-01-01

    As an appealing alternative to reference glucose analyzers, portable glucometers are recommended for self-monitoring at home, in the field, and in research settings. The purpose was to characterize the accuracy and precision, and bias of glucometers in biomedical research. Fifteen young (20-36 years; mean = 24.5), moderately to highly active men (n = 10) and women (n = 5), defined by exercising 2 to 3 times a week for the past 6 months, were given an oral glucose tolerance test (OGTT) after an overnight fast. Participants ingested 50, 75, or 150 grams of glucose over a 5-minute period. The glucometer was compared to a reference instrument. The glucometer had 39% of values within 15% of measurements made using the reference instrument ranging from 45.05 to 169.37 mg/dl. There was both a proportional (-0.45 to -0.39) and small fixed (5.06 and 0.90 mg/dl) bias. Results of the present study suggest that the glucometer provided poor validity and reliability results compared to the results provided by the reference laboratory analyzer. The portable glucometers should be used for patient management, but not for diagnosis, treatment, or research purposes. © 2014 Diabetes Technology Society.

  2. Striking against bioterrorism with advanced proteomics and reference methods.

    Science.gov (United States)

    Armengaud, Jean

    2017-01-01

    The intentional use by terrorists of biological toxins as weapons has been of great concern for many years. Among the numerous toxins produced by plants, animals, algae, fungi, and bacteria, ricin is one of the most scrutinized by the media because it has already been used in biocrimes and acts of bioterrorism. Improving the analytical toolbox of national authorities to monitor these potential bioweapons all at once is of the utmost interest. MS/MS allows their absolute quantitation and exhibits advantageous sensitivity, discriminative power, multiplexing possibilities, and speed. In this issue of Proteomics, Gilquin et al. (Proteomics 2017, 17, 1600357) present a robust multiplex assay to quantify a set of eight toxins in the presence of a complex food matrix. This MS/MS reference method is based on scheduled SRM and high-quality standards consisting of isotopically labeled versions of these toxins. Their results demonstrate robust reliability based on rather loose scheduling of SRM transitions and good sensitivity for the eight toxins, lower than their oral median lethal doses. In the face of an increased threat from terrorism, relevant reference assays based on advanced proteomics and high-quality companion toxin standards are reliable and firm answers. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Environmental reference materials methods and case studies

    DEFF Research Database (Denmark)

    Schramm-Nielsen, Karina Edith

    1998-01-01

    . This study lasted 22 months as well. The samples were produced and stored according to a 2³ factorial design. The influences of storage temperature, UV radiation and ultra-filtration on the stability of NH4-N and total phosphorous have been investigated. A Youden plot method is suggested for the graphical....... The methods have been evaluated with regard to their robustness towards variations in the chemical analytical method and with regard to the number of times a significant out of control situation is indicated. The second study regards the stability of NH4-N and total phosphorous in autoclaved seawater samples...... with wastewater. The purpose was to improve ortho-phosphate (and total phosphorous) homogeneity. A procedure is suggested which includes freeze-drying and redissolving. All calculations have been performed in SAS® primarily by means of elementary procedures, analyses of variance procedures, SAS Insight and SAS...

  4. Radioactive standards and calibration methods for contamination monitoring instruments

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Makoto [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-06-01

    Contamination monitoring in the facilities for handling unsealed radioactive materials is one of the most important procedures for radiation protection as well as radiation dose monitoring. For implementation of the proper contamination monitoring, radiation measuring instruments should not only be suitable to the purpose of monitoring, but also be well calibrated for the objective qualities of measurement. In the calibration of contamination monitoring instruments, quality reference activities need to be used. They are supplied in different such as extended sources, radioactive solutions or radioactive gases. These reference activities must be traceable to the national standards or equivalent standards. On the other hand, the appropriate calibration methods must be applied for each type of contamination monitoring instruments. In this paper, the concepts of calibration for contamination monitoring instruments, reference sources, determination methods of reference quantities and practical calibration methods of contamination monitoring instruments, including the procedures carried out in Japan Atomic Energy Research Institute and some relevant experimental data. (G.K.)

  5. 28 CFR 45.1 - Cross-reference to ethical standards and financial disclosure regulations.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Cross-reference to ethical standards and...) EMPLOYEE RESPONSIBILITIES § 45.1 Cross-reference to ethical standards and financial disclosure regulations. Employees of the Department of Justice are subject to the executive branch-wide Standards of Ethical Conduct...

  6. Standard Relativistic Reference Systems and the IAU Framework

    Science.gov (United States)

    Soffel, Michael H.

    2009-05-01

    The classical post-Newtonian (PN) framework is formulated in one single reference system. In a series of papers Damour, Soffel and Xu laid the foundations for a new improved PN framework dealing with the celestial mechanical problem of N gravitationally interacting rotating bodies of arbitrary shape and the problem of astronomical reference systems. In the DSX-framework a total of N+1 reference systems with corresponding coordinates is introduced in the N-body problem: a global one covering the entire model manifold where the translational equations of motion are formulated and one local system attached to each of the N bodies that is co-moving with the body under consideration. In each of these systems the metric tensor is assumed to be of a special form determined by two potentials: a scalar and a vector potential. Theorems are given for the transformations between local and global coordinates and metric potentials. In each of the local systems outside the local body the metric potentials are expressed in terms of Blanchet-Damour mass- and spin-multipole moments. The talk first introduces the original DSX formalism and then concentrates on IAU resolutions related with it. Finally, the formalism is extended to include also effects from the cosmic expansion. The influence of the Hubble expansion on the dynamics of the solar system is explicitly discussed in some detail.

  7. New International Reference Standards of Voltage and Resistance.

    Science.gov (United States)

    Sirvastava, V. P.

    1991-01-01

    The introduction of the quantum standards of resistance and voltage, based on the Quantum Hall Effect (QHE) and the Josephson Effect, can be used to establish highly reproducible and uniform representations of the ohm and volt worldwide. Discussed are the QHE and the Josephson Effect. (KR)

  8. Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This specification describes the physical requirements for primary and secondary terrestrial nonconcentrator photovoltaic reference cells. A reference cell is defined as a device that meets the requirements of this specification and is calibrated in accordance with Test Method E1125 or Test Method E1362. 1.2 Reference cells are used in the determination of the electrical performance of photovoltaic devices, as stated in Test Methods E948 and E1036. 1.3 Two reference cell physical specifications are described: 1.3.1 Small-Cell Package Design—A small, durable package with a low thermal mass, wide optical field-of-view, and standardized dimensions intended for photovoltaic devices up to 20 by 20 mm, and 1.3.2 Module-Package Design—A package intended to simulate the optical and thermal properties of a photovoltaic module design, but electric connections are made to only one photovoltaic cell in order to eliminate problems with calibrating series and parallel connections of cells. Physical dimensions ...

  9. Iodine in different food articles and standard reference materials

    International Nuclear Information System (INIS)

    Dermelj, M.; Slejkovec, Z.; Byrne, A.R.; Stegnar, P.; Stibilj, V.; Rossbach, M.

    1990-01-01

    The greater part of essential iodine enters living organisms via the food chain. Nevertheless, quantitative data on its concentration in diets, food articles and also in available SRMs are very poor and scarce. This and WHO recommendations on daily allowances of iodine for man via food articles caused an added demand for accurate and reliable determination of iodine in these samples. From this point of view the purpose of the present was to analyse and to establish the concentration levels of total iodine in some food articles, diets, SRMs and candidate reference materials by the use of rapid radiochemical separation, developed in our laboratory. The results were checked by the analysis of SRMs with available certified values for iodine and good agreement is evident. (orig.)

  10. A Standardized Reference Data Set for Vertebrate Taxon Name Resolution.

    Science.gov (United States)

    Zermoglio, Paula F; Guralnick, Robert P; Wieczorek, John R

    2016-01-01

    Taxonomic names associated with digitized biocollections labels have flooded into repositories such as GBIF, iDigBio and VertNet. The names on these labels are often misspelled, out of date, or present other problems, as they were often captured only once during accessioning of specimens, or have a history of label changes without clear provenance. Before records are reliably usable in research, it is critical that these issues be addressed. However, still missing is an assessment of the scope of the problem, the effort needed to solve it, and a way to improve effectiveness of tools developed to aid the process. We present a carefully human-vetted analysis of 1000 verbatim scientific names taken at random from those published via the data aggregator VertNet, providing the first rigorously reviewed, reference validation data set. In addition to characterizing formatting problems, human vetting focused on detecting misspelling, synonymy, and the incorrect use of Darwin Core. Our results reveal a sobering view of the challenge ahead, as less than 47% of name strings were found to be currently valid. More optimistically, nearly 97% of name combinations could be resolved to a currently valid name, suggesting that computer-aided approaches may provide feasible means to improve digitized content. Finally, we associated names back to biocollections records and fit logistic models to test potential drivers of issues. A set of candidate variables (geographic region, year collected, higher-level clade, and the institutional digitally accessible data volume) and their 2-way interactions all predict the probability of records having taxon name issues, based on model selection approaches. We strongly encourage further experiments to use this reference data set as a means to compare automated or computer-aided taxon name tools for their ability to resolve and improve the existing wealth of legacy data.

  11. A Standardized Reference Data Set for Vertebrate Taxon Name Resolution.

    Directory of Open Access Journals (Sweden)

    Paula F Zermoglio

    Full Text Available Taxonomic names associated with digitized biocollections labels have flooded into repositories such as GBIF, iDigBio and VertNet. The names on these labels are often misspelled, out of date, or present other problems, as they were often captured only once during accessioning of specimens, or have a history of label changes without clear provenance. Before records are reliably usable in research, it is critical that these issues be addressed. However, still missing is an assessment of the scope of the problem, the effort needed to solve it, and a way to improve effectiveness of tools developed to aid the process. We present a carefully human-vetted analysis of 1000 verbatim scientific names taken at random from those published via the data aggregator VertNet, providing the first rigorously reviewed, reference validation data set. In addition to characterizing formatting problems, human vetting focused on detecting misspelling, synonymy, and the incorrect use of Darwin Core. Our results reveal a sobering view of the challenge ahead, as less than 47% of name strings were found to be currently valid. More optimistically, nearly 97% of name combinations could be resolved to a currently valid name, suggesting that computer-aided approaches may provide feasible means to improve digitized content. Finally, we associated names back to biocollections records and fit logistic models to test potential drivers of issues. A set of candidate variables (geographic region, year collected, higher-level clade, and the institutional digitally accessible data volume and their 2-way interactions all predict the probability of records having taxon name issues, based on model selection approaches. We strongly encourage further experiments to use this reference data set as a means to compare automated or computer-aided taxon name tools for their ability to resolve and improve the existing wealth of legacy data.

  12. Reference depth for geostrophic computation - A new method

    Digital Repository Service at National Institute of Oceanography (India)

    Varkey, M.J.; Sastry, J.S.

    Various methods are available for the determination of reference depth for geostrophic computation. A new method based on the vertical profiles of mean and variance of the differences of mean specific volume anomaly (delta x 10) for different layers...

  13. Measurement of susceptibility artifacts with histogram-based reference value on magnetic resonance images according to standard ASTM F2119.

    Science.gov (United States)

    Heinrich, Andreas; Teichgräber, Ulf K; Güttler, Felix V

    2015-12-01

    The standard ASTM F2119 describes a test method for measuring the size of a susceptibility artifact based on the example of a passive implant. A pixel in an image is considered to be a part of an image artifact if the intensity is changed by at least 30% in the presence of a test object, compared to a reference image in which the test object is absent (reference value). The aim of this paper is to simplify and accelerate the test method using a histogram-based reference value. Four test objects were scanned parallel and perpendicular to the main magnetic field, and the largest susceptibility artifacts were measured using two methods of reference value determination (reference image-based and histogram-based reference value). The results between both methods were compared using the Mann-Whitney U-test. The difference between both reference values was 42.35 ± 23.66. The difference of artifact size was 0.64 ± 0.69 mm. The artifact sizes of both methods did not show significant differences; the p-value of the Mann-Whitney U-test was between 0.710 and 0.521. A standard-conform method for a rapid, objective, and reproducible evaluation of susceptibility artifacts could be implemented. The result of the histogram-based method does not significantly differ from the ASTM-conform method.

  14. Physical Fitness Reference Standards in French Youth: The BOUGE Program.

    Science.gov (United States)

    Vanhelst, Jérémy; Labreuche, Julien; Béghin, Laurent; Drumez, Elodie; Fardy, Paul S; Chapelot, Didier; Mikulovic, Jacques; Ulmer, Zékya

    2017-06-01

    The aim of this study was to establish sex- and age-specific physical fitness percentiles in French youth. A sample of 11,186 children and adolescents (5,546 boys and 5,640 girls), aged between 10 and 15 years, was assessed in the French national BOUGE study. Participants were tested for their cardiorespiratory fitness, muscular endurance, speed, flexibility, and agility using the following tests: 20-m shuttle run tests, curl-ups test, 50-m sprint test, back-saver sit and reach test, and 10 × 5-m shuttle run test. Percentile values were estimated for French youth as a function of age stratified by sex using the generalized additive model for location, scale, and shape (GAMLSS). In general, physical fitness was better in boys than in girls, except for the back-saver sit and reach test, in which girls performed better. Except for the back-saver sit and reach test and 10 × 5-m shuttle run test, physical fitness performance was significantly associated with age. Sex- and age-specific normative values for physical fitness tests in French youth expressed as percentiles from the fifth to the 95th are provided. Reference values provide normative data for French youth. The data are useful in identifying special needs for appropriate intervention programs.

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

    Science.gov (United States)

    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 HNO 3 acid after elution of matrix elements, including the other platinum group elements (PGE), in dilute HCl and HNO 3 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

  16. Reference design for the standard mirror hybrid reactor

    Energy Technology Data Exchange (ETDEWEB)

    Bender, D.J.; Fink, J.H.; Galloway, T.R.; Kastenberg, W.E.; Lee, J.D.; Devoto, R.S.; Neef, W.S. Jr.; Schultz, K.R.; Culver, D.W.; Rao, S.B.; Rao, S.R.

    1978-05-22

    This report describes the results of a two-year study by Lawrence Livermore Laboratory and General Atomic Co. to develop a conceptual design for the standard (minimum-B) mirror hybrid reactor. The reactor parameters have been chosen to minimize the cost of producing nuclear fuel (/sup 239/Pu) for consumption in fission power reactors (light water reactors). The deuterium-tritium plasma produces approximately 400 MW of fusion power with a plasma Q of 0.64. The fast-fission blanket, which is fueled with depleted uranium and lithium, generates sufficient tritium to run the reactor, has a blanket energy multiplication of M = 10.4, and has a net fissile breeding ratio of Pu/n = 1.51. The reactor has a net electrical output of 600 MWe, a fissile production of 2000 kg of plutonium per year (at a capacity factor of 0.74), and a net plant efficiency of 0.18. The plasma-containment field is generated by a Yin-Yang magnet using NbTi superconductor, and the neutral beam system uses positive-ion acceleration with beam direct conversion. The spherical blanket is based on gas-cooled fast reactor technology. The fusion components, blanket, and primary heat-transfer loop components are all contained within a prestressed-concrete reactor vessel, which provides magnet restraint and supports the primary heat-transfer loop and the blanket.

  17. Reference design for the standard mirror hybrid reactor

    International Nuclear Information System (INIS)

    Bender, D.J.; Fink, J.H.; Galloway, T.R.; Kastenberg, W.E.; Lee, J.D.; Devoto, R.S.; Neef, W.S. Jr.; Schultz, K.R.; Culver, D.W.; Rao, S.B.; Rao, S.R.

    1978-01-01

    This report describes the results of a two-year study by Lawrence Livermore Laboratory and General Atomic Co. to develop a conceptual design for the standard (minimum-B) mirror hybrid reactor. The reactor parameters have been chosen to minimize the cost of producing nuclear fuel ( 239 Pu) for consumption in fission power reactors (light water reactors). The deuterium-tritium plasma produces approximately 400 MW of fusion power with a plasma Q of 0.64. The fast-fission blanket, which is fueled with depleted uranium and lithium, generates sufficient tritium to run the reactor, has a blanket energy multiplication of M = 10.4, and has a net fissile breeding ratio of Pu/n = 1.51. The reactor has a net electrical output of 600 MWe, a fissile production of 2000 kg of plutonium per year (at a capacity factor of 0.74), and a net plant efficiency of 0.18. The plasma-containment field is generated by a Yin-Yang magnet using NbTi superconductor, and the neutral beam system uses positive-ion acceleration with beam direct conversion. The spherical blanket is based on gas-cooled fast reactor technology. The fusion components, blanket, and primary heat-transfer loop components are all contained within a prestressed-concrete reactor vessel, which provides magnet restraint and supports the primary heat-transfer loop and the blanket

  18. Calibrating NIST SRM 683 as A New International Reference Standard for Zn Isotopes

    Science.gov (United States)

    Yang, Y.; Zhang, X.; Yu, H.; Huang, F.

    2017-12-01

    Zinc isotopes have been widely applied in the cosmochemical, geochemical, and environmental studies (Moynier et al. 2017). Obtaining precise Zn isotopic data for inter-laboratory comparison is a prerequisite to these applications. Currently, the JMC3-0749L is the primary reference standard for Zn isotopes (Albarède 2004), but it is not commercially available now. Thus, it is necessary to calibrate a new international primary reference standard for Zn isotopic analysis. Chen et al. (2016) showed that NIST SRM 683 (a pure Zn metal nugget of 140 grams) has a δ66ZnJMC of 0.12‰, which is falling within the range of natural Zn isotopic compositions, and it may a good candidate for the next generation of international reference standard (Chen et al. 2016). In order to further examine whether NIST SRM 683 has a homogeneous Zn isotopic composition, we measured more NIST SRM 683 by double-spike methods using MC-ICPMS (Conway et al. 2013). The metal nuggets of NIST SRM 683 were intensively sampled by micro-drilling. Zinc isotope analyses for two nuggets show that they have δ66Zn of 0.14 ± 0.02‰ (2SD, N = 32) and 0.13 ± 0.02‰ (2SD, N = 33), respectively. These values are similar to those of two Zn metal nuggets (0.11 ± 0.02‰ vs. 0.12 ± 0.02‰) reported previously by Chen et al. (2016). We fully dissolved one nugget, producing pure Zn solution with identical Zn isotopic composition with the drilling samples. All results strongly support that NIST SRM 683 is homogeneous in Zn isotopic compositions which could be an ideal candidate for the next reference for Zn isotopes. Tests on more metal nuggets will be performed in a few months for further confirming the Zn isotope compositions and homogeneity. Reference: Albarède et al., 2004. 'The stable isotope geochemistry of copper and zinc', Reviews in Mineralogy and Geochemistry, 55: 409-27. Chen et al., 2016. 'Zinc Isotopic Compositions of NIST SRM 683 and Whole-Rock Reference Materials', Geostandards and

  19. Effect of Transitioning from Standard Reference Material 2806a to Standard Reference Material 2806b for Light Obscuration Particle Countering

    Science.gov (United States)

    2016-04-01

    gravimetric mass limits. The light obscuration particle counters utilized to perform this testing are calibrated to ISO 11171, Hydraulic fluid power...Calibration of automatic particle counters for liquids (2) and operated according to the following test methods : • IP 564: Determination of the...level of cleanliness of aviation turbine fuel - Laboratory automatic particle counter method (3) • IP 565: Determination of the level of cleanliness of

  20. [Comparison of susceptibility artifacts generated by microchips with different geometry at 1.5 Tesla magnet resonance imaging. A phantom pilot study referring to the ASTM standard test method F2119-07].

    Science.gov (United States)

    Dengg, S; Kneissl, S

    2013-01-01

    Ferromagnetic material in microchips, used for animal identification, causes local signal increase, signal void or distortion (susceptibility artifact) on MR images. To measure the impact of microchip geometry on the artifact's size, an MRI phantom study was performed. Microchips of the labels Datamars®, Euro-I.D.® and Planet-ID® (n  =  15) were placed consecutively in a phantom and examined with respect to the ASTM Standard Test Method F2119-07 using spin echo (TR 500 ms, TE 20 ms), gradient echo (TR 300 ms, TE 15 ms, flip angel 30°) and otherwise constant imaging parameters (slice thickness 3 mm, field of view 250 x 250 mm, acquisition matrix 256 x 256 pixel, bandwidth 32 kHz) at 1.5 Tesla. Image acquisition was undertaken with a microchip positioned in the x- and z-direction and in each case with a phase-encoding direction in the y- and z-direction. The artifact size was determined with a) a measurement according to the test method F2119-07 using a homogeneous point operation, b) signal intensity measurement according to Matsuura et al. and c) pixel counts in the artifact according to Port and Pomper. There was a significant difference in artifact size between the three microchips tested (Wilcoxon p = 0.032). A two- to three-fold increase in microchip volume generated an up to 76% larger artifact, depending on the sequence type, phase-encoding direction and chip position to B0. The smaller the microchip geometry, the less is the susceptibility artifact. Spin echoes (SE) generated smaller artifacts than gradient echoes (GE). In relation to the spatial measurement of the artifact, the switch in phase-encoding direction had less influence on the artifact size in GE- than in SE-sequences. However, the artifact shape and direction of SE-sequences can be changed by altering the phase. The artifact size, caused by the microchip, plays a major clinical role in the evaluation of MRI from the head, shoulder and neck regions.

  1. The stability of uranium microspheres for future application as reference standard in analytical measurements

    Energy Technology Data Exchange (ETDEWEB)

    Middendorp, R.; Duerr, M.; Bosbach, D. [Forschungszentrum Juelich GmbH, IEK-6, 52428 Juelich (Germany)

    2016-07-01

    The monitoring of fuel-cycle facilities provides a tool to confirm the compliant operation, for example with respect to emissions into the environment or to supervise non-proliferation commitments. Hereby, anomalous situations can be detected in a timely manner and responsive action can be initiated to prevent an escalation into an event of severe consequence to society. In order to verify non-nuclear weapon states' compliance with the non-proliferation treaty (NPT), international authorities such as the International Atomic Energy Agency (IAEA) conduct inspections at facilities dealing with fissile or fertile nuclear materials. One measure consists of collection of swipe samples through inspectors for later analysis of collected nuclear material traces in the laboratory. Highly sensitive mass spectrometric methods provide a means to detect traces from nuclear material handling activities that provide indication of undeclared use of the facility. There are, however, no relevant (certified) reference materials available that can be used as calibration or quality control standards. Therefore, an aerosol-generation based process was established at Forschungszentrum Juelich for the production of spherical, mono-disperse uranium oxide micro-particles with accurately characterized isotopic compositions and amounts of uranium in the pico-gram range. The synthesized particles are studied with respect to their suitability as (certified) reference material in ultra-trace analysis. Several options for preparation and stabilization of the particles are available, where preparation of particles in suspension offers the possibility to produces specific particle mixtures. In order to assess the stability of particles, dissolution behavior and isotope exchange effects of particles in liquid suspension is studied on the bulk of suspended particles and also via micro-analytical methods applied for single particle characterization. The insights gained within these studies will

  2. Palm-Based Standard Reference Materials for Iodine Value and Slip Melting Point

    Directory of Open Access Journals (Sweden)

    Azmil Haizam Ahmad Tarmizi

    2008-01-01

    Full Text Available This work described study protocols on the production of Palm-Based Standard Reference Materials for iodine value and slip melting point. Thirty-three laboratories collaborated in the inter-laboratory proficiency tests for characterization of iodine value, while thirty-two laboratories for characterization of slip melting point. The iodine value and slip melting point of palm oil, palm olein and palm stearin were determined in accordance to MPOB Test Methods p3.2:2004 and p4.2:2004, respectively. The consensus values and their uncertainties were based on the acceptability of statistical agreement of results obtained from collaborating laboratories. The consensus values and uncertainties for iodine values were 52.63 ± 0.14 Wijs in palm oil, 56.77 ± 0.12 Wijs in palm olein and 33.76 ± 0.18 Wijs in palm stearin. For the slip melting points, the consensus values and uncertainties were 35.6 ± 0.3 ° C in palm oil, 22.7 ± 0.4 ° C in palm olein and 53.4 ± 0.2 ° C in palm stearin. Repeatability and reproducibility relative standard deviations were found to be good and acceptable, with values much lower than that of 10%. Stability of Palm-Based Standard Reference Materials remained stable at temperatures of -20 ° C, 0 ° C, 6 ° C and 24 ° C upon storage for one year.

  3. Quantitative micro x-ray fluorescence analyses without reference standard material; Referenzprobenfreie quantitative Mikro-Roentgenfluoreszenzanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, Timo

    2009-07-15

    X-ray fluorescence analysis (XRF) is a standard method for non-destructive investigations. Due to the development of polycapillary optics and SDDdetectors requiring no cooling with liquid nitrogen, XRF becomes a suitable method for a large number of applications, e. g. for the analysis of objects in arts and archaeology. Spectrometers developed for those purposes allow investigations outside of laboratories und provide excitation areas with diameters of 10-70 {mu}m. In most applications, quantification of XRF data is realized by the usage of standard reference materials. Due to absorption processes in the samples the accuracy of the results depends strongly on the similarity of the sample and the reference standard. In cases where no suitable references are available, quantification can be done based on the ''fundamental parameter (fp) method''. This quantification procedure is based on a set of equations describing the fluorescence production and detection mathematical. The cross sections for the interaction of x-rays with matter can be taken from different databases. During an iteration process the element concentrations can be determined. Quantitative XRF based on fundamental parameters requires an accurate knowledge of the excitation spectrum. In case of a conventional setup this spectrum is given by the X-ray tube spectrum and can be calculated. The use of polycapillary optics in micro-XRF spectrometers changes the spectral distribution of the excitation radiation. For this reason it is necessary to access the transmission function of the used optic. The aim of this work is to find a procedure to describe this function for routine quantification based on fundamental parameters. Most of the measurements have been carried out using a commercial spectrometer developed for applications in arts and archaeology. On the one hand the parameters of the lens, used in the spectrometer, have been investigated by different experimental characterization

  4. Comparison Between a Reference Torque Standard Machine and a Deadweight Torque Standard Machine to BE Used in Torque Calibration

    Science.gov (United States)

    Meng, Feng; Zhang, Zhimin; Lin, Jing

    The paper describes the reference torque standard machine with high accuracy and multifunction, developed by our institute, and introduces the structure and working principle of this machine. It has three main functions. The first function is the hydraulic torque wrench calibration function. The second function is torque multiply calibration function. The third function is reference torque standard machine function. We can calibrate the torque multipliers, hydraulic wrenches and transducers by this machine. A comparison experiment has been done between this machine and a deadweight torque standard machine. The consistency between the 30 kNm reference torque machine and the 2000 Nm dead-weight torque standard machine under the claimed uncertainties was verified.

  5. Indirect methods for reference interval determination - review and recommendations.

    Science.gov (United States)

    Jones, Graham R D; Haeckel, Rainer; Loh, Tze Ping; Sikaris, Ken; Streichert, Thomas; Katayev, Alex; Barth, Julian H; Ozarda, Yesim

    2018-04-19

    Reference intervals are a vital part of the information supplied by clinical laboratories to support interpretation of numerical pathology results such as are produced in clinical chemistry and hematology laboratories. The traditional method for establishing reference intervals, known as the direct approach, is based on collecting samples from members of a preselected reference population, making the measurements and then determining the intervals. An alternative approach is to perform analysis of results generated as part of routine pathology testing and using appropriate statistical techniques to determine reference intervals. This is known as the indirect approach. This paper from a working group of the International Federation of Clinical Chemistry (IFCC) Committee on Reference Intervals and Decision Limits (C-RIDL) aims to summarize current thinking on indirect approaches to reference intervals. The indirect approach has some major potential advantages compared with direct methods. The processes are faster, cheaper and do not involve patient inconvenience, discomfort or the risks associated with generating new patient health information. Indirect methods also use the same preanalytical and analytical techniques used for patient management and can provide very large numbers for assessment. Limitations to the indirect methods include possible effects of diseased subpopulations on the derived interval. The IFCC C-RIDL aims to encourage the use of indirect methods to establish and verify reference intervals, to promote publication of such intervals with clear explanation of the process used and also to support the development of improved statistical techniques for these studies.

  6. 18 CFR 1300.101 - Cross references to employee ethical conduct standards and other applicable regulations.

    Science.gov (United States)

    2010-04-01

    ... employee ethical conduct standards and other applicable regulations. 1300.101 Section 1300.101 Conservation... TENNESSEE VALLEY AUTHORITY § 1300.101 Cross references to employee ethical conduct standards and other...-wide standards of ethical conduct at 5 CFR part 2635 and to the TVA regulations at 5 CFR part 7901...

  7. 46 CFR 164.023-3 - Specifications and standards incorporated by reference.

    Science.gov (United States)

    2010-10-01

    ... are: Federal Standards and Test Method Standards The following test methods in Federal Test Method Standard No. 191A, Textile Test Methods, July 20, 1978: (1) Method 4010, Length-Weight Relation; Thread..., Polyester Core: Cotton-, Rayon-, or Polyester-Covered, September 30, 1986—164.023-5. (7) MIL-T-43624A—Thread...

  8. Reactor Section standard analytical methods. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Sowden, D.

    1954-07-01

    the Standard Analytical Methods manual was prepared for the purpose of consolidating and standardizing all current analytical methods and procedures used in the Reactor Section for routine chemical analyses. All procedures are established in accordance with accepted practice and the general analytical methods specified by the Engineering Department. These procedures are specifically adapted to the requirements of the water treatment process and related operations. The methods included in this manual are organized alphabetically within the following five sections which correspond to the various phases of the analytical control program in which these analyses are to be used: water analyses, essential material analyses, cotton plug analyses boiler water analyses, and miscellaneous control analyses.

  9. Setting the standard: The IAEA safety standards set the global reference

    International Nuclear Information System (INIS)

    Williams, L.

    2003-01-01

    For the IAEA, setting and promoting standards for nuclear radiation, waste, and transport safety have been priorities from the start, rooted in the Agency's 1957 Statute. Today, a corpus of international standards are in place that national regulators and industries in many countries are applying, and more are being encouraged and assisted to follow them. Considerable work is done to keep safety standards updated and authoritative. They cover five main areas: the safety of nuclear facilities; radiation protection and safety of radiation sources; safe management of radioactive waste; safe transport of radioactive material; and thematic safety areas, such as emergency preparedness or legal infrastructures. Overall, the safety standards reflect an international consensus on what constitutes a high level of safety for protecting people and the environment. All IAEA Member States can nominate experts for the Agency standards committees and provide comments on draft standards. Through this ongoing cycle of review and feedback, the standards are refined, updated, and extended where needed

  10. A Comparative Study of Standardized Infinity Reference and Average Reference for EEG of Three Typical Brain States

    Directory of Open Access Journals (Sweden)

    Gaoxing Zheng

    2018-03-01

    Full Text Available The choice of different reference electrodes plays an important role in deciphering the functional meaning of electroencephalography (EEG signals. In recent years, the infinity zero reference using the reference electrode standard technique (REST has been increasingly applied, while the average reference (AR was generally advocated as the best available reference option in previous classical EEG studies. Here, we designed EEG experiments and performed a direct comparison between the influences of REST and AR on EEG-revealed brain activity features for three typical brain behavior states (eyes-closed, eyes-open and music-listening. The analysis results revealed the following observations: (1 there is no significant difference in the alpha-wave-blocking effect during the eyes-open state compared with the eyes-closed state for both REST and AR references; (2 there was clear frontal EEG asymmetry during the resting state, and the degree of lateralization under REST was higher than that under AR; (3 the global brain functional connectivity density (FCD and local FCD have higher values for REST than for AR under different behavior states; and (4 the value of the small-world network characteristic in the eyes-closed state is significantly (in full, alpha, beta and gamma frequency bands higher than that in the eyes-open state, and the small-world effect under the REST reference is higher than that under AR. In addition, the music-listening state has a higher small-world network effect than the eyes-closed state. The above results suggest that typical EEG features might be more clearly presented by applying the REST reference than by applying AR when using a 64-channel recording.

  11. Agreement between diagnoses reached by clinical examination and available reference standards: a prospective study of 216 patients with lumbopelvic pain

    Directory of Open Access Journals (Sweden)

    Tropp Hans

    2005-06-01

    Full Text Available Abstract Background The tissue origin of low back pain (LBP or referred lower extremity symptoms (LES may be identified in about 70% of cases using advanced imaging, discography and facet or sacroiliac joint blocks. These techniques are invasive and availability varies. A clinical examination is non-invasive and widely available but its validity is questioned. Diagnostic studies usually examine single tests in relation to single reference standards, yet in clinical practice, clinicians use multiple tests and select from a range of possible diagnoses. There is a need for studies that evaluate the diagnostic performance of clinical diagnoses against available reference standards. Methods We compared blinded clinical diagnoses with diagnoses based on available reference standards for known causes of LBP or LES such as discography, facet, sacroiliac or hip joint blocks, epidurals injections, advanced imaging studies or any combination of these tests. A prospective, blinded validity design was employed. Physiotherapists examined consecutive patients with chronic lumbopelvic pain and/or referred LES scheduled to receive the reference standard examinations. When diagnoses were in complete agreement regardless of complexity, "exact" agreement was recorded. When the clinical diagnosis was included within the reference standard diagnoses, "clinical agreement" was recorded. The proportional chance criterion (PCC statistic was used to estimate agreement on multiple diagnostic possibilities because it accounts for the prevalence of individual categories in the sample. The kappa statistic was used to estimate agreement on six pathoanatomic diagnoses. Results In a sample of chronic LBP patients (n = 216 with high levels of disability and distress, 67% received a patho-anatomic diagnosis based on available reference standards, and 10% had more than one tissue origin of pain identified. For 27 diagnostic categories and combinations, chance clinical agreement

  12. SITE SPECIFIC REFERENCE PERSON PARAMETERS AND DERIVED CONCENTRATION STANDARDS FOR THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, T.

    2013-03-14

    The purpose of this report is twofold. The first is to develop a set of behavioral parameters for a reference person specific for the Savannah River Site (SRS) such that the parameters can be used to determine dose to members of the public in compliance with Department of Energy (DOE) Order 458.1 “Radiation Protection of the Public and the Environment.” A reference person is a hypothetical, gender and age aggregation of human physical and physiological characteristics arrived at by international consensus for the purpose of standardizing radiation dose calculations. DOE O 458.1 states that compliance with the annual dose limit of 100 mrem (1 mSv) to a member of the public may be demonstrated by calculating the dose to the maximally exposed individual (MEI) or to a representative person. Historically, for dose compliance, SRS has used the MEI concept, which uses adult dose coefficients and adult male usage parameters. Beginning with the 2012 annual site environmental report, SRS will be using the representative person concept for dose compliance. The dose to a representative person will be based on 1) the SRS-specific reference person usage parameters at the 95th percentile of appropriate national or regional data, which are documented in this report, 2) the reference person (gender and age averaged) ingestion and inhalation dose coefficients provided in DOE Derived Concentration Technical Standard (DOE-STD-1196-2011), and 3) the external dose coefficients provided in the DC_PAK3 toolbox. The second purpose of this report is to develop SRS-specific derived concentration standards (DCSs) for all applicable food ingestion pathways, ground shine, and water submersion. The DCS is the concentration of a particular radionuclide in water, in air, or on the ground that results in a member of the public receiving 100 mrem (1 mSv) effective dose following continuous exposure for one year. In DOE-STD-1196-2011, DCSs were developed for the ingestion of water, inhalation of

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

    Science.gov (United States)

    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.

  14. Standard Test Method for Sandwich Corrosion Test

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method defines the procedure for evaluating the corrosivity of aircraft maintenance chemicals, when present between faying surfaces (sandwich) of aluminum alloys commonly used for aircraft structures. This test method is intended to be used in the qualification and approval of compounds employed in aircraft maintenance operations. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information. 1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements appear in Section 9.

  15. Statistical methods for evaluating the attainment of cleanup standards

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, R.O.; Simpson, J.C.

    1992-12-01

    This document is the third volume in a series of volumes sponsored by the US Environmental Protection Agency (EPA), Statistical Policy Branch, that provide statistical methods for evaluating the attainment of cleanup Standards at Superfund sites. Volume 1 (USEPA 1989a) provides sampling designs and tests for evaluating attainment of risk-based standards for soils and solid media. Volume 2 (USEPA 1992) provides designs and tests for evaluating attainment of risk-based standards for groundwater. The purpose of this third volume is to provide statistical procedures for designing sampling programs and conducting statistical tests to determine whether pollution parameters in remediated soils and solid media at Superfund sites attain site-specific reference-based standards. This.document is written for individuals who may not have extensive training or experience with statistical methods. The intended audience includes EPA regional remedial project managers, Superfund-site potentially responsible parties, state environmental protection agencies, and contractors for these groups.

  16. Quantification of the predominant monomeric catechins in baking chocolate standard reference material by LC/APCI-MS.

    Science.gov (United States)

    Nelson, Bryant C; Sharpless, Katherine E

    2003-01-29

    Catechins are polyphenolic plant compounds (flavonoids) that may offer significant health benefits to humans. These benefits stem largely from their anticarcinogenic, antioxidant, and antimutagenic properties. Recent epidemiological studies suggest that the consumption of flavonoid-containing foods is associated with reduced risk of cardiovascular disease. Chocolate is a natural cocoa bean-based product that reportedly contains high levels of monomeric, oligomeric, and polymeric catechins. We have applied solid-liquid extraction and liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometry to the identification and determination of the predominant monomeric catechins, (+)-catechin and (-)-epicatechin, in a baking chocolate Standard Reference Material (NIST Standard Reference Material 2384). (+)-Catechin and (-)-epicatechin are detected and quantified in chocolate extracts on the basis of selected-ion monitoring of their protonated [M + H](+) molecular ions. Tryptophan methyl ester is used as an internal standard. The developed method has the capacity to accurately quantify as little as 0.1 microg/mL (0.01 mg of catechin/g of chocolate) of either catechin in chocolate extracts, and the method has additionally been used to certify (+)-catechin and (-)-epicatechin levels in the baking chocolate Standard Reference Material. This is the first reported use of liquid chromatography/mass spectrometry for the quantitative determination of monomeric catechins in chocolate and the only report certifying monomeric catechin levels in a food-based Standard Reference Material.

  17. The evaluation of accuracy of NAA method used by P2TRR laboratory with food standard reference material analysis; Evaluasi akurasi lab. AAN P2TRR dengan analisis cuplikan standar acuan bahan makanan

    Energy Technology Data Exchange (ETDEWEB)

    Rina M, Th; Sri-Wardhani,; Sunarko, [Center for Development of Research Reactor Technology (Indonesia)

    2003-05-15

    The NAA method is the analysis method with high precision and accuracy level. The precision and accuracy of NAA laboratory in P2TRR had been evaluated with SRM 1573a Tomato Leaf and CRM No.9 Sargasso. Samples were irradiated in RSG-GAS's rabbit system and counted with gamma spectrometry. The results obtained from this research are for the SRM 1573a sample the test could analyze 17 elements of the 40 certified elements, and for CRM No.9 sample the test could analyze 16 elements of the 30 certified elements. The result of quantitative analysis indicate the different deviation of each element between 2 -10.5 % compared to the certificate data. This deviation value <15%, this value shows that the precision and accuracy level is good enough.

  18. Referring to IAEA system to improve Chinese standards system on nuclear and radiation safety

    International Nuclear Information System (INIS)

    Shang Zhaorong; Wang Wenhai

    2010-01-01

    Referring to the standards system of IAEA, to build and improve the Chinese standards system of nuclear and radiation safety is a long term infrastructure work and an assurance to keep sustainable development of nuclear industry and nuclear technology application in China. The paper analyses the current main problem, and gives some suggestions on developing and improving the system. (authors)

  19. Compilation of elemental concentration data for NBS Biological and Environmental Standard Reference Materials

    International Nuclear Information System (INIS)

    Gladney, E.S.

    1980-07-01

    Concentration data on up to 76 elementals in 19 NBS Standard Reference Materials have been collected from 325 journal articles and technical reports. These data are summarized into mean +- one standard deviation values and compared with available data from NBS and other review articles. Data are presented on the analytical procedures employed and all raw data are presented in appendixes

  20. Palm-Based Standard Reference Materials for Iodine Value and Slip Melting Point

    Directory of Open Access Journals (Sweden)

    Azmil Haizam Ahmad Tarmizi

    2008-01-01

    Full Text Available This work described study protocols on the production of Palm-Based Standard Reference Materials for iodine value and slip melting point. Thirty-three laboratories collaborated in the inter-laboratory proficiency tests for characterization of iodine value, while thirty-two laboratories for characterization of slip melting point. The iodine value and slip melting point of palm oil, palm olein and palm stearin were determined in accordance to MPOB Test Methods p3.2:2004 and p4.2:2004, respectively. The consensus values and their uncertainties were based on the acceptability of statistical agreement of results obtained from collaborating laboratories. The consensus values and uncertainties for iodine values were 52.63 ± 0.14 Wijs in palm oil, 56.77 ± 0.12 Wijs in palm olein and 33.76 ± 0.18 Wijs in palm stearin. For the slip melting points, the consensus values and uncertainties were 35.6 ± 0.3 °C in palm oil, 22.7 ± 0.4 °C in palm olein and 53.4 ± 0.2 °C in palm stearin. Repeatability and reproducibility relative standard deviations were found to be good and acceptable, with values much lower than that of 10%. Stability of Palm-Based Standard Reference Materials remained stable at temperatures of –20 °C, 0 °C, 6 °C and 24 °C upon storage for one year.

  1. Establishing the traceability of a uranyl nitrate solution to a standard reference material

    International Nuclear Information System (INIS)

    Jackson, C.H.; Clark, J.P.

    1978-01-01

    A uranyl nitrate solution for use as a Working Calibration and Test Material (WCTM) was characterized, using a statistically designed procedure to document traceability to National Bureau of Standards Reference Material (SPM-960). A Reference Calibration and Test Material (PCTM) was prepared from SRM-960 uranium metal to approximate the acid and uranium concentration of the WCTM. This solution was used in the characterization procedure. Details of preparing, handling, and packaging these solutions are covered. Two outside laboratories, each having measurement expertise using a different analytical method, were selected to measure both solutions according to the procedure for characterizing the WCTM. Two different methods were also used for the in-house characterization work. All analytical results were tested for statistical agreement before the WCTM concentration and limit of error values were calculated. A concentration value was determined with a relative limit of error (RLE) of approximately 0.03% which was better than the target RLE of 0.08%. The use of this working material eliminates the expense of using SRMs to fulfill traceability requirements for uranium measurements on this type material. Several years' supply of uranyl nitrate solution with NBS traceability was produced. The cost of this material was less than 10% of an equal quantity of SRM-960 uranium metal

  2. [Classification of Colombian children with malnutrition according to NCHS reference or WHO standard].

    Science.gov (United States)

    Velásquez, Claudia; Bermúdez, Juliana; Echeverri, Claudia; Estrada, Alejandro

    2011-12-01

    A descriptive study was conducted to evaluate the concordance of National Center for Health Statistics reference (NCHS) used to classify undernourished children from Colombia with the WHO Child Growth Standards. We used data from children aged 6 to 59 months with acute malnutrition (Z Infantil" nutrition program in Colombia. Indicators height-for-age, weight for-height were analyzed when they were admitted to the hospital and weight for-height leaving the hospital. A statistical method used to compare means was T-student. Correlation coefficient intraclass (CCI) and Kappa index evaluated the concordance between NCHS and OMS; McNemar method evaluated the changes on the nutritional classification for children according to growth devices used. Of the total number of children classified as normal by NCHS, 10.4% were classified as stunted by WHO. 64% of the children admitted to the hospital presented acute malnutrition according to NCHS, of these 44,8% presented severe emaciation according to OMS, indeed severe emaciation increased of 36,0% to 63,3% using OMS. 5% of children leaving the hospital could need to stay more days if they had been evaluated with OMS. Growth devices shown high concordance in height-for-age (CCI = 0,988; k= 0,866) and weight for-height (CCI = 0,901; k = 0,578). Concluded that OMS growth standards classified more malnourished children and more severe states, in addition more malnourished children could be hospitalized and they could stay more days.

  3. A simple method for HPLC retention time prediction: linear calibration using two reference substances.

    Science.gov (United States)

    Sun, Lei; Jin, Hong-Yu; Tian, Run-Tao; Wang, Ming-Juan; Liu, Li-Na; Ye, Liu-Ping; Zuo, Tian-Tian; Ma, Shuang-Cheng

    2017-01-01

    Analysis of related substances in pharmaceutical chemicals and multi-components in traditional Chinese medicines needs bulk of reference substances to identify the chromatographic peaks accurately. But the reference substances are costly. Thus, the relative retention (RR) method has been widely adopted in pharmacopoeias and literatures for characterizing HPLC behaviors of those reference substances unavailable. The problem is it is difficult to reproduce the RR on different columns due to the error between measured retention time (t R ) and predicted t R in some cases. Therefore, it is useful to develop an alternative and simple method for prediction of t R accurately. In the present study, based on the thermodynamic theory of HPLC, a method named linear calibration using two reference substances (LCTRS) was proposed. The method includes three steps, procedure of two points prediction, procedure of validation by multiple points regression and sequential matching. The t R of compounds on a HPLC column can be calculated by standard retention time and linear relationship. The method was validated in two medicines on 30 columns. It was demonstrated that, LCTRS method is simple, but more accurate and more robust on different HPLC columns than RR method. Hence quality standards using LCTRS method are easy to reproduce in different laboratories with lower cost of reference substances.

  4. Reference interval computation: which method (not) to choose?

    Science.gov (United States)

    Pavlov, Igor Y; Wilson, Andrew R; Delgado, Julio C

    2012-07-11

    When different methods are applied to reference interval (RI) calculation the results can sometimes be substantially different, especially for small reference groups. If there are no reliable RI data available, there is no way to confirm which method generates results closest to the true RI. We randomly drawn samples obtained from a public database for 33 markers. For each sample, RIs were calculated by bootstrapping, parametric, and Box-Cox transformed parametric methods. Results were compared to the values of the population RI. For approximately half of the 33 markers, results of all 3 methods were within 3% of the true reference value. For other markers, parametric results were either unavailable or deviated considerably from the true values. The transformed parametric method was more accurate than bootstrapping for sample size of 60, very close to bootstrapping for sample size 120, but in some cases unavailable. We recommend against using parametric calculations to determine RIs. The transformed parametric method utilizing Box-Cox transformation would be preferable way of RI calculation, if it satisfies normality test. If not, the bootstrapping is always available, and is almost as accurate and precise as the transformed parametric method. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. MOISTURE IN COTTON BY THE KARL FISCHER TITRATION REFERENCE METHOD

    Science.gov (United States)

    Moisture is a critical parameter that influences many aspects of cotton fiber from harvesting and ginning to various fiber properties. Because of their importance, reference moisture methods that are more accurate than the existing oven-drying techniques and relatively easy to generate results are ...

  6. A preliminary comparative study on the content of cesium, thorium and uranium in IAEA standard reference material

    International Nuclear Information System (INIS)

    Zhang Jing; Liu Husheng; Wang Xiaoyan; Wang Naifen

    2000-01-01

    This paper presents the detection of Cs, Th and U in 6 standard reference materials provided by IAEA, using the ICP-MS method. The bismuth (Bi) was selected as internal standard element for the range compensation of matrix inhibitory effect and flow of the sensibility. The detection limit of the 3 elements was limited in the range of 0.0006∼2ng/ml, 0.4∼0.5g sample was taken and digested by acid, and detected directly by ICP-MS. The recovery of standard addition was 82.1∼100.1%

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

    Science.gov (United States)

    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

  8. Dual reference point temperature interrogating method for distributed temperature sensor

    International Nuclear Information System (INIS)

    Ma, Xin; Ju, Fang; Chang, Jun; Wang, Weijie; Wang, Zongliang

    2013-01-01

    A novel method based on dual temperature reference points is presented to interrogate the temperature in a distributed temperature sensing (DTS) system. This new method is suitable to overcome deficiencies due to the impact of DC offsets and the gain difference in the two signal channels of the sensing system during temperature interrogation. Moreover, this method can in most cases avoid the need to calibrate the gain and DC offsets in the receiver, data acquisition and conversion. An improved temperature interrogation formula is presented and the experimental results show that this method can efficiently estimate the channel amplification and system DC offset, thus improving the system accuracy. (letter)

  9. EPA flow reference method testing and analysis: Findings report

    International Nuclear Information System (INIS)

    1999-06-01

    This report describes an experimental program sponsored by the US Environmental Protection Agency (EPA) to evaluate potential improvements to the Agency's current reference method for measuring volumetric flow (Method 2, 40 CFR Part 60, Appendix B). Method 2 (Determination of Stack Gas Velocity and Volumetric Flow Rate (Type S Pitot Tube)) specifies measurements to determine volumetric flow, but does not prescribe specific procedures to account for yaw or pitch angles of flow when the flow in the stack is not axial. Method 2 also allows the use of only two probe types, the Type S and the Prandtl

  10. Mixed gamma emitting gas standard and method

    International Nuclear Information System (INIS)

    McFarland, R.C.; McFarland, P.A.

    1986-01-01

    The invention in one aspect pertains to a method of calibrating gamma spectroscopy systems for gas counting in a variety of counting containers comprising withdrawing a precision volume of a mixed gamma-emitting gas standard from a precision volume vial and delivering the withdrawn precision volume of the gas standard to the interior of a gas counting container. Another aspect of the invention pertains to a mixed gamma-emitting gas standard, comprising a precision spherical vial of predetermined volume, multiple mixed emitting gas components enclosed within the vial, and means for withdrawing from the vial a predetermined amount of the components wherein the gas standard is used to calibrate a gamma spectrometer system for gas counting over a wide energy range without the use of additional standards. A third aspect comprehends a gamma spectrometer calibration system for gas counting, comprising a precision volume spherical glass vial for receiving mixed multiisotope gas components, and two tubular arms extending from the vial. A ground glass stopcock is positioned on each arm, and the outer end of one arm is provided with a rubber septum port

  11. Determination of multielement in optical waveguide and standard reference materials by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Kobayashi, K.; Kudo, K.

    1979-01-01

    Trace amounts of transition elements (Co, Cr, Cu, Fe, Mn and V) and other seven elements in optical waveguide samples were determined by INAA. The contents of impurities in ultre-pure materials are less than those of high-purity materials and of G.R. grade. The increase of contamination of trace transition elements and iridium from furnace or crucible are observed in the production of optical glass fibers. Up to seventeen elements were determined in five NBS biological standard reference materials: Oyster Tissue: SRM-1566, Brewers Yeast: SRM-1569, Spinach: SRM-1570, Orchard Leaves: SRM-1571 and Tuna Fish, and in four Japanese biological standard reference materials: Tea Leaves B and C, Pepperbush and Shark Meat. The analytical results in NBS and Japanese standard reference materials are in good agreement with published values and certified values by NBS. (author)

  12. Standard digital reference images for investment steel castings for aerospace applications

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 The digital reference images provided in the adjunct to this standard illustrate various types and degrees of discontinuities occurring in thin-wall steel investment castings. Use of this standard for the specification or grading of castings requires procurement of the adjunct digital reference images which illustrate the discontinuity types and severity levels. They are intended to provide the following: 1.1.1 A guide enabling recognition of thin-wall steel casting discontinuities and their differentiation both as to type and degree through digital radiographic examination. 1.1.2 Example digital radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications and drawings. 1.2 Two illustration categories are covered as follows: 1.2.1 Graded—Six common discontinuity types each illustrated in eight degrees of progressively increasing severity. 1.2.2 Ungraded—Twelve single illustrations of additional discontinuity types and of patterns and imper...

  13. Method of evaluation of diagnostics reference levels in computerized tomography

    International Nuclear Information System (INIS)

    Vega, Walter Flores

    1999-04-01

    Computerized tomography is a complex technique with several selectable exposition parameters delivering high doses to the patient. In this work it was developed a simple methodology to evaluate diagnostic reference levels in computerized tomography, using the concept of Multiple Scan Average Dose (MSAD), recently adopted by the Health Ministry. For evaluation of the MSAD, a dose distribution was obtained through a measured dose profile on the axial axis of a water phantom with thermoluminescence dosemeters, TLD-100, for different exam technique. The MSAD was evaluated hrough two distinct methods. First, it was evaluated by the integration of the dose profile of a single slice and, second, obtained by the integration on central slice of the profile of several slices. The latter is in of accordance with the ionization chamber method, suggesting to be the most practical method of dose evaluation to be applied in the diagnostic reference level assessment routine for CT, using TLDs. (author)

  14. New birth weight reference standards customised to birth order and sex of babies from South India

    Directory of Open Access Journals (Sweden)

    Kumar Velusamy Saravana

    2013-02-01

    Full Text Available Abstract Background The foetal growth standards for Indian children which are available today suffer due to methodological problems. These are, for example, not adhering to the WHO recommendation to base gestational age on the number of completed weeks and secondly, not excluding mothers with risk factors. This study has addressed both the above issues and in addition provides birthweight reference ranges with regard to sex of the baby and maternal parity. Methods Data from the labour room register from 1996 to 2010 was obtained. A rotational sampling scheme was used i.e. the 12 months of the year were divided into 4 quadrants. All deliveries in January were considered to represent the first quadrant. Similarly all deliveries in April, July and October were considered to represent 2nd, 3rd and 4th quadrants. In each successive year different months were included in each quadrant. Only those mothers aged 20–39 years and delivered between 24 to 42 weeks gestational age were considered. Those mothers with obstetric risk factors were excluded. The reference standards were fitted using the Generalized Additive Models for Location Scale and Shape (GAMLSS method for Box – Cox t distribution with cubic spline smoothing. Results There were 41,055 deliveries considered. When women with risk factors were excluded 19,501 deliveries could be included in the final analysis. The male babies of term firstborn were found to be 45 g heavier than female babies. The mean birthweights were 2934 g and 2889.5 g respectively. Similarly, among the preterm babies, the first born male babies weighed 152 g more than the female babies. The mean birthweights were 1996 g and 1844 g respectively. In the case of later born babies, the term male babies weighed 116grams more than the females. The mean birth weights were 3085 grams and 2969 grams respectively. When considering later born preterm babies, the males outweighed the female babies by 111 grams. The

  15. Implementation of a reference standard and proficiency testing programme by the World Wide Antimalarial Resistance Network (WWARN

    Directory of Open Access Journals (Sweden)

    Barnes Karen I

    2010-12-01

    Full Text Available Abstract Background The Worldwide Antimalarial Resistance Network (WWARN is a global collaboration to support the objective that anyone affected by malaria receives effective and safe drug treatment. The Pharmacology module aims to inform optimal anti-malarial drug selection. There is an urgent need to define the drug exposure - effect relationship for most anti-malarial drugs. Few anti-malarials have had their therapeutic blood concentration levels defined. One of the main challenges in assessing safety and efficacy data in relation to drug concentrations is the comparability of data generated from different laboratories. To explain differences in anti-malarial pharmacokinetics in studies with different measurement laboratories it is necessary to confirm the accuracy of the assay methods. This requires the establishment of an external quality assurance process to assure results that can be compared. This paper describes this process. Methods The pharmacology module of WWARN has established a quality assurance/quality control (QA/QC programme consisting of two separate components: 1. A proficiency testing programme where blank human plasma spiked with certified reference material (CRM in different concentrations is sent out to participating bioanalytical laboratories. 2. A certified reference standard programme where accurately weighed amounts of certified anti-malarial reference standards, metabolites, and internal standards are sent to participating bioanalytical and in vitro laboratories. Conclusion The proficiency testing programme is designed as a cooperative effort to help participating laboratories assess their ability to carry out drug analysis, resolve any potential problem areas and to improve their results - and, in so doing, to improve the quality of anti-malarial pharmacokinetic data published and shared with WWARN. By utilizing the same source of standards for all laboratories, it is possible to minimize bias arising from poor

  16. Milk and serum standard reference materials for monitoring organic contaminants in human samples.

    Science.gov (United States)

    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.

  17. The use of high accuracy NAA for the certification of NIST botanical standard reference materials

    International Nuclear Information System (INIS)

    Becker, D.A.; Greenberg, R.R.; Stone, S.F.

    1992-01-01

    Neutron activation analysis is one of many analytical techniques used at the National Institute of Standards and Technology (NIST) for the certification of NIST Standard Reference Materials (SRMs). NAA competes favorably with all other techniques because of it's unique capabilities for high accuracy even at very low concentrations for many elements. In this paper, instrumental and radiochemical NAA results are described for 25 elements in two new NIST SRMs, SRM 1515 (Apple Leaves) and SRM 1547 (Peach Leaves), and are compared to the certified values for 19 elements in these two new botanical reference materials. (author) 7 refs.; 4 tabs

  18. New birth weight reference standards customised to birth order and sex of babies from South India.

    Science.gov (United States)

    Kumar, Velusamy Saravana; Jeyaseelan, Lakshmanan; Sebastian, Tunny; Regi, Annie; Mathew, Jiji; Jose, Ruby

    2013-02-14

    The foetal growth standards for Indian children which are available today suffer due to methodological problems. These are, for example, not adhering to the WHO recommendation to base gestational age on the number of completed weeks and secondly, not excluding mothers with risk factors. This study has addressed both the above issues and in addition provides birthweight reference ranges with regard to sex of the baby and maternal parity. Data from the labour room register from 1996 to 2010 was obtained. A rotational sampling scheme was used i.e. the 12 months of the year were divided into 4 quadrants. All deliveries in January were considered to represent the first quadrant. Similarly all deliveries in April, July and October were considered to represent 2nd, 3rd and 4th quadrants. In each successive year different months were included in each quadrant. Only those mothers aged 20-39 years and delivered between 24 to 42 weeks gestational age were considered. Those mothers with obstetric risk factors were excluded. The reference standards were fitted using the Generalized Additive Models for Location Scale and Shape (GAMLSS) method for Box-Cox t distribution with cubic spline smoothing. There were 41,055 deliveries considered. When women with risk factors were excluded 19,501 deliveries could be included in the final analysis. The male babies of term firstborn were found to be 45 g heavier than female babies. The mean birthweights were 2934 g and 2889.5 g respectively. Similarly, among the preterm babies, the first born male babies weighed 152 g more than the female babies. The mean birthweights were 1996 g and 1844 g respectively.In the case of later born babies, the term male babies weighed 116 grams more than the females. The mean birth weights were 3085 grams and 2969 grams respectively. When considering later born preterm babies, the males outweighed the female babies by 111 grams. The mean birthweights were 2089 grams and 1978 grams

  19. Evaluation of a new 10 mA DC current reference standard

    CERN Document Server

    Fernqvist, G; Power, F

    2002-01-01

    A new DC current reference standard has been developed as a component in a Current calibration hierarchy in the LHC project at CERN. The standard provides 10 mA DC current with an accuracy less than 0.5 ppm, drift less than 2 ppm/year and compliance error less than 0.1 ppm for 0-10 V. The paper gives the results from two years evaluation of a series of 5 units.

  20. Reference neutron radiations. Part 1: Characteristics and methods of production

    International Nuclear Information System (INIS)

    2001-01-01

    ISO 8529 consists of the following parts, under the general title Reference neutron radiations: Part 1: Characteristics and methods of production; Part 2: Calibration fundamentals of radiation protection devices related to the basic quantities characterizing the radiation field; Part 3: Calibration of area and personal dosimeters and determination of response as a function of energy and angle of incidence. This Part 1. of ISO 8529 specifies the reference neutron radiations, in the energy range from thermal up to 20 MeV, for calibrating neutron-measuring devices used for radiation protection purposes and for determining their response as a function of neutron energy. Reference radiations are given for neutron fluence rates of up to 1x10 9 m 2 s-1 , corresponding, at a neutron energy of 1 MeV, to dose-equivalent rates of up to 100 mSv h -1 . This part of ISO 8529 is concerned only with the methods of producing and characterizing the neutron reference radiations. The procedures for applying these radiations for calibrations are described in ISO 8529-2 and ISO 8529-3. The reference radiations specified are the following: neutrons from radionuclide sources, including neutrons from sources in a moderator; neutrons produced by nuclear reactions with charged particles from accelerators; neutrons from reactors. In view of the methods of production and use of them, these reference radiations are divided, for the purposes of this part of ISO 8529, into the following two separate sections. In clause 4, radionuclide neutron sources with wide spectra are specified for the calibration of neutron measuring devices. These sources should be used by laboratories engaged in the routine calibration of neutron-measuring devices, the particular design of which has already been type tested. In clause 5, accelerator-produced monoenergetic neutrons and reactor-produced neutrons with wide or quasi monoenergetic spectra are specified for determining the response of neutron-measuring devices

  1. The NIST natural-matrix radionuclide standard reference material program for ocean studies

    International Nuclear Information System (INIS)

    Inn, K.G.W.; Zhichao Lin; Zhongyu Wu; MacMahon, C.; Filliben, J.J.; Krey, P.; Feiner, M.; Harvey, J.

    2001-01-01

    In 1997, the Low-level Working Group of the International Committee on Radionuclide Metrology met in Boston, MA (USA) to define the characteristics of a new set of environmental radioactivity reference materials. These reference materials were to provide the radiochemist with the same analytical challenges faced when assaying environmental samples. It was decided that radionuclide bearing natural materials should be collected from sites where there had been sufficient time for natural processes to redistribute the various chemically different species of the radionuclides. Over the succeeding years, the National Institute of Standards and Technology (NIST), in cooperation with other highly experienced laboratories, certified and issued a number of these as low-level radioactivity Standard Reference Materials (SRMs) for fission and activation product and actinide concentrations. The experience of certifying these SRMs has given NIST the opportunity to compare radioanalytical methods and learn of their limitations. NIST convened an international workshop in 1994 to define the natural-matrix radionuclide SRM needs for ocean studies. The highest priorities proposed at the workshop were for sediment, shellfish, seaweed, fish flesh and water matrix SRMs certified for mBq per sample concentrations of 90 Sr, 137 Cs and 239 Pu + 240 Pu. The most recent low-level environmental radionuclide SRM issued by NIST, Ocean Sediment (SRM 4357) has certified and uncertified values for the following 22 radionuclides: 40 K, 90 Sr, 129 I, 137 Cs, 155 Eu, 210 Pb, 210 Po, 212 Pb, 214 Bi, 226 Ra, 228 Ra, 228 Th, 230 Th, 232 Th, 234 U, 235 U, 237 Np, 238 U, 238 Pu, 239 Pu + 240 Pu, and 241 Am. The uncertainties for a number of the certified radionuclides are non-symmetrical and relatively large because of the non-normal distribution of reported values. NIST is continuing its efforts to provide the ocean studies community with additional natural matrix radionuclide SRMs. The freeze

  2. 34 CFR 73.1 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Cross-reference to employee ethical conduct standards... of Education STANDARDS OF CONDUCT § 73.1 Cross-reference to employee ethical conduct standards and... branch-wide Standards of Ethical Conduct at 5 CFR part 2635 and to the Department of Education regulation...

  3. Towards Automatic Testing of Reference Point Based Interactive Methods

    OpenAIRE

    Ojalehto, Vesa; Podkopaev, Dmitry; Miettinen, Kaisa

    2016-01-01

    In order to understand strengths and weaknesses of optimization algorithms, it is important to have access to different types of test problems, well defined performance indicators and analysis tools. Such tools are widely available for testing evolutionary multiobjective optimization algorithms. To our knowledge, there do not exist tools for analyzing the performance of interactive multiobjective optimization methods based on the reference point approach to communicating ...

  4. A method to calibrate a solar pyranometer for measuring reference diffuse irradiance

    Energy Technology Data Exchange (ETDEWEB)

    Reda, I.; Stoffel, T.; Myers, D. [National Renewable Energy Laboratory, Golden, CO (United States)

    2003-02-01

    Accurate pyranometer calibrations, traceable to internationally recognized standards, are critical for solar irradiance measurements. One calibration method is the component summation, where the pyranometers are calibrated outdoors under clear sky conditions, and the reference global solar irradiance is calculated as the sum of two reference components, the diffuse and subtended beam solar irradiances. The beam component is measured with pyrheliometers traceable to the World Radiometric Reference, while there is no internationally recognized reference for the diffuse component. In the absence of such a reference, we present a method to consistently calibrate pyranometers for measuring the diffuse component with an estimated uncertainty of {+-} (3% of reading +1 W/m{sup 2}). The method is based on using a modified shade/unshade method, and pyranometers with less than 1 W/m{sup 2} thermal offset errors. We evaluated the consistency of our method by calibrating three pyranometers four times. Calibration results show that the responsivity change is within {+-} 0.52% for the three pyranometers. We also evaluated the effect of calibrating pyranometers unshaded, then using them shaded to measure diffuse irradiance. We calibrated three unshaded pyranometers using the component summation method. Their outdoor measurements of clear sky diffuse irradiance, from sunrise to sundown, showed that the three calibrated pyranometers can be used to measure the diffuse irradiance to within {+-} 1.4 W/m{sup 2} variation from the reference irradiance. (author)

  5. Comparação entre os métodos de referência e a análise eletrônica na determinação da composição do leite bovino Comparison between standard methods and electronic analyses for measurement of the bovine milk composition

    Directory of Open Access Journals (Sweden)

    T.M.L. Silveira

    2004-12-01

    Full Text Available Avaliou-se a metodologia de determinação da composição do leite por meio de analisador de infravermelho, utilizando-se 48 amostras individuais de leite de vacas da raça Holandesa e cinco amostras de leite de conjunto. A média dos resultados para gordura, proteína, lactose e sólidos totais das amostras individuais foram, respectivamente, 3,8%, 3,3%, 4,6% e 12,4%, usando-se metodologia de referência e 3,8%, 3,3%, 4,5% e 12,4%, usando-se equipamento eletrônico. Para amostras de tanque, as médias foram 3,9% e 4,0% para gordura, 3,2% e 3,2% para proteína, 4,7% e 4,6% para lactose e 12,6% e 12,6% para sólidos totais, respectivamente, para análises feitas por métodos de referência e por analisador de infravermelho. Não houve diferença (P>0,05 entre os valores das duas análises. Foi avaliada a qualidade das amostras-padrão canadense e americano, determinando-se os teores de gordura, proteína, lactose e sólidos totais por métodos de referência. Os resultados foram comparados com os valores declarados no laudo de análise das amostras, emitidos pelo laboratório fornecedor.In order to evaluate an electronic method for determination of milk composition based on infrared determination, 48 raw milk samples from Holstein cows and five bulk tank samples were analyzed for fat, protein, lactose and total solids contents. Results for fat, protein, lactose, and total solids contents for raw milk samples were, respectively, 3.8%, 3.3%, 4.6% and 12.4% using the standard methods, and 3.8%, 3.3%, 4.5%, and 12.4%, using electronic equipment. For the bulk tank samples results for fat, protein, lactose and total solids contents were, respectively, 3.9%, 3.2%, 4.7%, and 12.6% using the standard methods, and 4.0%, 3.2%, 4.6%, and 12.6% using electronic equipment. No differences between values obtained from both analytical methods were observed (P>0.05. The quality of the American and Canadian standard samples was evaluated by determination of fat

  6. One directional polarized neutron reflectometry with optimized reference layer method

    International Nuclear Information System (INIS)

    Masoudi, S. Farhad; Jahromi, Saeed S.

    2012-01-01

    In the past decade, several neutron reflectometry methods for determining the modulus and phase of the complex reflection coefficient of an unknown multilayer thin film have been worked out among which the method of variation of surroundings and reference layers are of highest interest. These methods were later modified for measurement of the polarization of the reflected beam instead of the measurement of the intensities. In their new architecture, these methods not only suffered from the necessity of change of experimental setup but also another difficulty was added to their experimental implementations. This deficiency was related to the limitations of the technology of the neutron reflectometers that could only measure the polarization of the reflected neutrons in the same direction as the polarization of the incident beam. As the instruments are limited, the theory has to be optimized so that the experiment could be performed. In a recent work, we developed the method of variation of surroundings for one directional polarization analysis. In this new work, the method of reference layer with polarization analysis has been optimized to determine the phase and modulus of the unknown film with measurement of the polarization of the reflected neutrons in the same direction as the polarization of the incident beam.

  7. Standard reference data for the air-liquid and vapor-liquid surface tension of benzene

    Czech Academy of Sciences Publication Activity Database

    Součková, Monika; Klomfar, Jaroslav; Pátek, Jaroslav

    2013-01-01

    Roč. 356, October (2013), s. 329-337 ISSN 0378-3812 R&D Projects: GA ČR GA101/09/0010 Institutional support: RVO:61388998 Keywords : benzene * surface tension * experimental data * standard reference data Subject RIV: BJ - Thermodynamics Impact factor: 2.241, year: 2013 http://www.sciencedirect.com/science/article/pii/S0378381213004196

  8. Body Parameters of Czech Breastfed Children Compared to the Czech References and WHO Growth Standards

    Czech Academy of Sciences Publication Activity Database

    Riedlová, J.; Vignerová, J.; Paulová, M.; Musil, V.; Brabec, Marek; Schneidrová, D.

    2017-01-01

    Roč. 44, č. 7 (2017), s. 593-599 ISSN 0301-4460 Grant - others:GA MZd(CZ) NS9974 Institutional support: RVO:67985807 Keywords : breastfed children * Czech reference * Growth charts * WHO growth standards Subject RIV: BB - Applied Statistics, Operational Research OBOR OECD: Statistics and probability Impact factor: 1.240, year: 2016

  9. 78 FR 57293 - Distribution of Reference Biological Standards and Biological Preparations

    Science.gov (United States)

    2013-09-18

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES 42 CFR Part 7 [Docket No. CDC-2013-0013] RIN 0920-AA52 Distribution of Reference Biological Standards and Biological Preparations AGENCY: Centers for Disease Control and Prevention (HHS/CDC), Department of Health and Human Services (HHS). ACTION: Confirmation of...

  10. 78 FR 47319 - Fee Schedule for Reference Biological Standards and Biological Preparations

    Science.gov (United States)

    2013-08-05

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention Fee Schedule for Reference Biological Standards and Biological Preparations AGENCY: Centers for Disease Control and... for Disease Control and Prevention (CDC), located within the Department of Health and Human Services...

  11. Normalization Methods and Selection Strategies for Reference Materials in Stable Isotope Analyses - Review

    International Nuclear Information System (INIS)

    Skrzypek, G.; Sadler, R.; Paul, D.; Forizs, I.

    2011-01-01

    A stable isotope analyst has to make a number of important decisions regarding how to best determine the 'true' stable isotope composition of analysed samples in reference to an international scale. It has to be decided which reference materials should be used, the number of reference materials and how many repetitions of each standard is most appropriate for a desired level of precision, and what normalization procedure should be selected. In this paper we summarise what is known about propagation of uncertainties associated with normalization procedures and propagation of uncertainties associated with reference materials used as anchors for the determination of 'true' values for δ''1''3C and δ''1''8O. Normalization methods Several normalization methods transforming the 'raw' value obtained from mass spectrometers to one of the internationally recognized scales has been developed. However, as summarised by Paul et al. different normalization transforms alone may lead to inconsistencies between laboratories. The most common normalization procedures are: single-point anchoring (versus working gas and certified reference standard), modified single-point normalization, linear shift between the measured and the true isotopic composition of two certified reference standards, two-point and multipoint linear normalization methods. The accuracy of these various normalization methods has been compared by using analytical laboratory data by Paul et al., with the single-point and normalization versus tank calibrations resulting in the largest normalization errors, and that also exceed the analytical uncertainty recommended for δ 13 C. The normalization error depends greatly on the relative differences between the stable isotope composition of the reference material and the sample. On the other hand, the normalization methods using two or more certified reference standards produces a smaller normalization error, if the reference materials are bracketing the whole range of

  12. Design and evaluation of a 10-mA DC current reference standard

    CERN Document Server

    Fernqvist, G; Pickering, J; Power, F

    2003-01-01

    A new DC current reference standard has been developed for high- current power converter calibration in the large hadron collider (LHC) project at the European Organization for Nuclear Research (CERN). This standard provides a near ideal 10-mA DC current with long-term drift of one part in 10/sup 6/ per year. The paper describes the requirements and the detailed design and evaluation of the unit. Since similar 10-V standards are commercially available, the paper concentrates on the unique current output capability of this device. (4 refs).

  13. Construction of a new growth references for China based on urban Chinese children: comparison with the WHO growth standards.

    Science.gov (United States)

    Zong, Xin-Nan; Li, Hui

    2013-01-01

    Growth references for Chinese children should be updated due to the positive secular growth trends and the progress of the smoothing techniques. Human growth differs among the various ethnic groups, so comparison of the China references with the WHO standards helps to understand such differences. The China references, including weight, length/height, head circumference, weight-for-length/height and body mass index (BMI) aged 0-18 years, were constructed based on 69,760 urban infants and preschool children under 7 years and 24,542 urban school children aged 6-20 years derived from two cross-sectional national surveys. The Cole's LMS method is employed for smoothing the growth curves. The merged data sets resulted in a smooth transition at age 6-7 years and continuity of curves from 0 to 18 years. Varying differences were found on the empirical standard deviation (SD) curves in each indicator at nearly all ages between China and WHO. The most noticeable differences occurred in genders, final height and boundary centiles curves. Chinese boys' weight is strikingly heavier than that of the WHO at age 6-10 years. The height is taller than that of the WHO for boys below 15 years and for girls below 13, but is significantly lower when boys over 15 years and girls over 13. BMI is generally higher than that of the WHO for boys at age 6-16 years but appreciably lower for girls at 3-18 years. The differences between China and WHO are mainly caused by the reference populations of different ethnic backgrounds. For practitioners, the choices of the standards/references depend on the population to be assessed and the purpose of the study. The new China references could be applied to facilitate the standardization assessment of growth and nutrition for Chinese children and adolescents in clinical pediatric and public health.

  14. Determination of Impurities in Aluminum Alloy by INAA Single Comparator Method (K0-Standardization Method)

    International Nuclear Information System (INIS)

    Sarheel, A.; Khamis, I.; Somel, N.

    2007-01-01

    Multielement determination by the k0 based INAA using k0-IAEA program has been performed at Syrian Atomic Energy Commission using alloys. Concentrations of Cu, Zn, Fe, Ni, Sn and Ti in addition to aluminum element were determined in an aluminum alloy and Ni, Cr, Mo were determined in dental alloys using INAA k0-standardization method. Al-0.1%Au, Ni and Zn certified reference materials were analyzed to assess the suitability and accuracy of the method. Elements were determined in reference materials and samples after short and long irradiations, according to element half-lives.

  15. An endogenous standard, radioisotopic ratio method in NAA

    International Nuclear Information System (INIS)

    Byrne, A.R.; Dermelj, M.

    1997-01-01

    A derivative form of NAA is proposed which is based on the use of an endogenous internal standard of already known concentration in the sample. If a comparator with a known ratio of the determinand and endogenous standard are co-irradiated with the sample, the determinand concentration is derived in terms of the endogenous standard concentration and the activity ratios of the two induced nuclides in the sample and comparator. As well as eliminating the sample mass and greatly reducing errors caused by pulse pile-up and geometrical differences, it was shown that in the radiochemical mode, if the endogenous standard is chosen so that the induced activity is radioisotopic with that from the determinand, the radiochemical yield is also eliminated and the risk non-achievement of isotopic exchange greatly reduced. The method is demonstrated with good results on reference materials for the determination of I, Mn and Ni. The advantages and disadvantages of this approach are discussed. It is suggested that it may be of application in quality control and in extending the range of certified elements in reference materials. (author)

  16. Methods to estimate irrigated reference crop evapotranspiration - a review.

    Science.gov (United States)

    Kumar, R; Jat, M K; Shankar, V

    2012-01-01

    Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.

  17. 45 CFR 680.10 - Definitions; cross-references to employee ethical conduct standards and financial disclosure...

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Definitions; cross-references to employee ethical... Foundation § 680.10 Definitions; cross-references to employee ethical conduct standards and financial...-references to employee ethical conduct standards and financial disclosure regulations. Members of the...

  18. 49 CFR 1019.1 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Cross-reference to employee ethical conduct... Cross-reference to employee ethical conduct standards and financial disclosure regulations. Members and employees of the Surface Transportation Board also should refer to the executive branch Standards of Ethical...

  19. Determining the normal range for IGF-I, IGFBP-3, and ALS: new reference data based on current internal standards.

    Science.gov (United States)

    Ertl, Diana-Alexandra; Gleiss, Andreas; Sagmeister, Susanne; Haeusler, Gabriele

    2014-09-01

    The measurement of insulin-like growth factors (IGF-I) and insulin-like growth factor-binding protein (IGFBP-3) often serves as first-line testing in children with growth disorders. The role of acid-labile subunit (ALS) as a screening parameter for homozygous or heterozygous mutations of the ALS gene still has to be determined. IGF-I, IGFBP-3, and ALS were measured in 252 samples from children and adolescents. Reference curves were fitted using generalized additive model for location, scale and shape (GAMLSS) models and SD-Scores were calculated. Bootstrap analysis was used to quantify the uncertainty of the estimated percentiles. Bland-Altman plots were used to investigate the discrepancy between our newly estimated standard deviation scores (SDS) and SDS calculated on the basis of previous reference data. We present reference data for enzyme-linked immunosorbent assay (ELISA) measurements based on recommended internal standard for IGF-I, IGFBP-3, and ALS suitable for calculation of SD-scores. The Bland-Altman plot shows a rough agreement between the previous SDS calculation and our new one only for SDS around 1; for SDS at -2, an average difference of 0.83 SD was noticed. Our IGF-I reference values for the interval of interest in diagnosing growth hormone deficiency (GHD) (prepubertal age) are solid as proved by bootstrap analysis. The difference in calculated SD scores by using data provided previously highlights the importance of using labor and method specific reference data.

  20. 230Th-234U Model-Ages of Some Uranium Standard Reference Materials

    International Nuclear Information System (INIS)

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

    2009-01-01

    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 230 Th- 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 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 3 O 8 ) may be assumed with confidence. We present here 230 Th- 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. 230Th-234U Model-Ages of Some Uranium Standard Reference Materials

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Standardization of 18F by coincidence and LSC methods

    International Nuclear Information System (INIS)

    Roteta, Miguel; Garcia-Torano, Eduardo; Rodriguez Barquero, Leonor

    2006-01-01

    The nuclide 18 F disintegrates to 18 O by β + emission (96.86%) and electron capture (3.14%) with a half-life of 1.8288 h. It is widely used in nuclear medicine for positron emission tomography (PET). A radioactive solution of this nuclide has been standardized by two techniques: coincidence measurements with a pressurized proportional counter and liquid scintillation counting using the CIEMAT/NIST method. One ampoule containing a solution calibrated in activity was sent for measurement at the International Reference System maintained by the BIPM. Results are in excellent agreement with SIR values

  3. Comparison of the reference mark azimuth determination methods

    Directory of Open Access Journals (Sweden)

    Danijel Šugar

    2013-03-01

    Full Text Available The knowledge of the azimuth of the reference mark is of crucial importance in the determination of the declination which is defined as the ellipsoidal (geodetic azimuth of the geomagnetic meridian. The accuracy of the azimuth determination has direct impact on the accuracy of the declination. The orientation of the Declination-Inclination Magnetometer is usually carried out by sighting the reference mark in two telescope faces in order to improve the reliability of the observations and eliminate some instrumental errors. In this paper, different coordinate as well as azimuth determination methods using GNSS (Global Navigation Satellite System observation techniques within VPPS (High-Precision Positioning Service and GPPS (Geodetic-Precision Positioning Service services of the CROPOS (CROatian POsitioning System system were explained. The azimuth determination by the observation of the Polaris was exposed and it was subsequently compared with the observation of the Sun using hour-angle and zenith-distance method. The procedure of the calculation of the geodetic azimuth from the astronomic azimuth was explained. The azimuth results obtained by different methods were compared and the recommendations on the minimal distance between repeat station and azimuth mark were given. The results shown in this paper were based on the observations taken on the POKU_SV repeat station.

  4. Direct calibration of GC/MS systems using SRM (Standard Reference Material) gas cylinders. Project report, January 1984-August 1985

    International Nuclear Information System (INIS)

    Byrd, G.D.; Richie, K.L.; Sniegoski, L.T.; White, E.

    1985-10-01

    A cryogenic trapping system has been developed for use in calibrating GC/MS systems for the analysis of volatile organic compounds. This system provides for direct Standard Reference Material (SRM) traceability on data generated on gaseous samples. The cryogenic trap is a coil of stainless steel tubing immersed in a cryogen to trap and preconcentrate organic species present in a gaseous sample. The trap also contains a heated injection port for the addition of isotopically labeled compounds for use in isotope dilution measurements. The first part of this research is concerned with the development of IDMS as an independent method for the quantification of analytes in gaseous samples to be used as standards. Results are presented for the determination of bromobenzene in nitrogen at nominal concentrations of 1 and 25 ppb. In the second part of the research, a calibration curve method was developed for using these standards in auditing the performance of GC/MS systems

  5. Measuring the activity of BioBrick promoters using an in vivo reference standard

    Directory of Open Access Journals (Sweden)

    Kelly Jason R

    2009-03-01

    Full Text Available Abstract Background The engineering of many-component, synthetic biological systems is being made easier by the development of collections of reusable, standard biological parts. However, the complexity of biology makes it difficult to predict the extent to which such efforts will succeed. As a first practical example, the Registry of Standard Biological Parts started at MIT now maintains and distributes thousands of BioBrick™ standard biological parts. However, BioBrick parts are only standardized in terms of how individual parts are physically assembled into multi-component systems, and most parts remain uncharacterized. Standardized tools, techniques, and units of measurement are needed to facilitate the characterization and reuse of parts by independent researchers across many laboratories. Results We found that the absolute activity of BioBrick promoters varies across experimental conditions and measurement instruments. We choose one promoter (BBa_J23101 to serve as an in vivo reference standard for promoter activity. We demonstrated that, by measuring the activity of promoters relative to BBa_J23101, we could reduce variation in reported promoter activity due to differences in test conditions and measurement instruments by ~50%. We defined a Relative Promoter Unit (RPU in order to report promoter characterization data in compatible units and developed a measurement kit so that researchers might more easily adopt RPU as a standard unit for reporting promoter activity. We distributed a set of test promoters to multiple labs and found good agreement in the reported relative activities of promoters so measured. We also characterized the relative activities of a reference collection of BioBrick promoters in order to further support adoption of RPU-based measurement standards. Conclusion Relative activity measurements based on an in vivoreference standard enables improved measurement of promoter activity given variation in measurement

  6. A Meta-Analysis of Typhoid Diagnostic Accuracy Studies: A Recommendation to Adopt a Standardized Composite Reference.

    Directory of Open Access Journals (Sweden)

    Helen L Storey

    Full Text Available Novel typhoid diagnostics currently under development have the potential to improve clinical care, surveillance, and the disease burden estimates that support vaccine introduction. Blood culture is most often used as the reference method to evaluate the accuracy of new typhoid tests; however, it is recognized to be an imperfect gold standard. If no single gold standard test exists, use of a composite reference standard (CRS can improve estimation of diagnostic accuracy. Numerous studies have used a CRS to evaluate new typhoid diagnostics; however, there is no consensus on an appropriate CRS. In order to evaluate existing tests for use as a reference test or inclusion in a CRS, we performed a systematic review of the typhoid literature to include all index/reference test combinations observed. We described the landscape of comparisons performed, showed results of a meta-analysis on the accuracy of the more common combinations, and evaluated sources of variability based on study quality. This wide-ranging meta-analysis suggests that no single test has sufficiently good performance but some existing diagnostics may be useful as part of a CRS. Additionally, based on findings from the meta-analysis and a constructed numerical example demonstrating the use of CRS, we proposed necessary criteria and potential components of a typhoid CRS to guide future recommendations. Agreement and adoption by all investigators of a standardized CRS is requisite, and would improve comparison of new diagnostics across independent studies, leading to the identification of a better reference test and improved confidence in prevalence estimates.

  7. 18 CFR 38.2 - Incorporation by reference of North American Energy Standards Board Wholesale Electric Quadrant...

    Science.gov (United States)

    2010-04-01

    ... reference of North American Energy Standards Board Wholesale Electric Quadrant standards. 38.2 Section 38.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY... UTILITIES § 38.2 Incorporation by reference of North American Energy Standards Board Wholesale Electric...

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

    Science.gov (United States)

    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.

  9. Stability of Working Reference Standards for Hybrid K-Edge Densitometer Quality Assurance

    International Nuclear Information System (INIS)

    Guzzardo, T.; Pickett, C.A.; McElroy, R.; Croft, S.; Garrison, J.; Venkataraman, R.

    2015-01-01

    The relatively short working life of aqueous solution standards of actinides for the calibration and quality control of Hybrid K-Edge Densitometer (HKED) measurements necessitates the development of a stable matrix material less susceptible to degradation. Degradation in the form of evaporation, radiolysis, settling, sloshing, and sediment formation can all reduce the reliability and working life of an aqueous standard. These factors make aqueous solutions inadequate for long-term quality assurance measurements designed to detect weak or subtle trends in system performance. Epoxy, studied here, is an alternative matrix material that may be less vulnerable to degradation. An additional benefit of epoxy is that standards can easily be characterized as sealed sources which allows for simplified administrative controls during shipping and storage. The stability of working reference standards consisting of U 3 O 8 in an epoxy matrix for use in the HKED has been tracked for over three years through repeated X-ray Fluorescence (XRF) and K-Edge (KED) measurements. A set of six epoxy standards ranging in concentration from 1 g/l to 76 g/l uranium were determined to be stable, within the expected accuracy of the system, over the period of analysis. During this time, no effort was made to enhance the stability of the epoxy standards; the radial measurement position was not controlled and in the middle of the analysis period the HKED system and standards were shipped from the vendor's factory to the customer. Epoxy standards afford numerous benefits over those created from aqueous solutions and should be considered when developing HKED standards for quality assurance measurements. The stability of the epoxy allows the development of working standards of a stability and robustness sufficient for use in a proposed international round-robin exercise based on the exchange of such standards. (author)

  10. Generating method-specific Reference Ranges - A harmonious outcome?

    Science.gov (United States)

    Lee, Graham R; Griffin, Alison; Halton, Kieran; Fitzgibbon, Maria C

    2017-12-01

    When laboratory Reference Ranges (RR) do not reflect analytical methodology, result interpretation can cause misclassification of patients and inappropriate management. This can be mitigated by determining and implementing method-specific RRs, which was the main objective of this study. Serum was obtained from healthy volunteers (Male + Female, n > 120) attending hospital health-check sessions during June and July 2011. Pseudo-anonymised aliquots were stored (at - 70 °C) prior t° analysis on Abbott ARCHITECT c16000 chemistry and i 2000SR immunoassay analysers. Data were stratified by gender where appropriate. Outliers were excluded statistically (Tukey method) to generate non-parametric RRs (2.5th + 97.5th percentiles). RRs were compared to those quoted by Abbott and UK Pathology Harmony (PH) where possible. For 7 selected tests, RRs were verified using a data mining approach. For chemistry tests (n = 23), Upper or Lower Reference Limits (LRL or URL) were > 20% different from Abbott ranges in 25% of tests (11% from PH ranges) but in 38% for immunoassay tests (n = 13). RRs (mmol/L) for sodium (138-144), potassium (3.8-4.9) and chloride (102-110) were considerably narrower than PH ranges (133-146, 3.5-5.0 and 95-108, respectively). The gender difference for ferritin (M: 29-441, F: 8-193 ng/mL) was more pronounced than reported by Abbott (M: 22-275, F: 5-204 ng/mL). Verification studies showed good agreement for chemistry tests (mean [SD] difference = 0.4% [1.2%]) but less so for immunoassay tests (27% [29%]), particularly for TSH (LRL). Where resource permits, we advocate using method-specific RRs in preference to other sources, particularly where method bias and lack of standardisation limits RR transferability and harmonisation.

  11. Anthropometry as a tool for measuring malnutrition: impact of the new WHO growth standards and reference.

    Science.gov (United States)

    Duggan, M B

    2010-01-01

    Anthropometry is a useful tool, both for monitoring growth and for nutritional assessment. The publication by WHO of internationally agreed growth standards in 1983 facilitated comparative nutritional assessment and the grading of childhood malnutrition. New growth standards for children under 5 years and growth reference for children aged 5-19 years have recently (2006 and 2007) been published by WHO. Growth of children growth reference study involving children from six countries, selected for optimal child-rearing practices (breastfeeding, non-smoking mothers). They therefore constitute a growth standard. Growth data for older children were drawn from existing US studies, and upward skewing was avoided by excluding overweight subjects. These constitute a reference. More indicators are now included to describe optimal early childhood growth and development, e.g. BMI for age and MUAC for age. The growth reference for older children (2007) focuses on linear growth and BMI; weight-for-age data are age-limited and weight-for-height is omitted. Differences in the 2006 growth pattern from the previous reference for children toddler. The spread of values for height and weight for height is narrower in the 2006 dataset, such that the lower limit of the normal range for both indices is set higher than in the previous dataset. This means that a child will be identified as moderately or severely underweight for height (severe acute malnutrition) at a greater weight for height than previously. The implications for services for malnourished children have been recognised and strategies devised. The emphasis on BMI-for-age as the indicator for thinness and obesity in older children is discussed. The complexity of calculations for health cadres without mathematical backgrounds or access to calculation software is also an issue. It is possible that the required charts and tables may not be accessible to those working in traditional health/nutrition services which are often poorly

  12. A new large-volume metal reference standard for radioactive waste management.

    Science.gov (United States)

    Tzika, F; Hult, M; Stroh, H; Marissens, G; Arnold, D; Burda, O; Kovář, P; Suran, J; Listkowska, A; Tyminski, Z

    2016-03-01

    A new large-volume metal reference standard has been developed. The intended use is for calibration of free-release radioactivity measurement systems and is made up of cast iron tubes placed inside a box of the size of a Euro-pallet (80 × 120 cm). The tubes contain certified activity concentrations of (60)Co (0.290 ± 0.006 Bq g(-1)) and (110m)Ag (3.05 ± 0.09 Bq g(-1)) (reference date: 30 September 2013). They were produced using centrifugal casting from a smelt into which (60)Co was first added and then one piece of neutron irradiated silver wire was progressively diluted. The iron castings were machined to the desirable dimensions. The final material consists of 12 iron tubes of 20 cm outer diameter, 17.6 cm inner diameter, 40 cm length/height and 245.9 kg total mass. This paper describes the reference standard and the process of determining the reference activity values. © The Author 2015. Published by Oxford University Press.

  13. Measurement of polybrominated diphenyl ethers in environmental matrix standard reference materials

    Energy Technology Data Exchange (ETDEWEB)

    Stapleton, H.; Schantz, M.; Wise, S. (National Institute of Standards and Technology)

    2004-09-15

    Polybrominated diphenyl ethers (PBDEs) are a class of emerging contaminants of concern as many studies have now demonstrated that these compounds are bioaccumulative, persistent and increasing in concentration in the environment. PBDEs are being detected in almost every environmental sample examined, and they have even been measured in samples collected in the Arctic, further demonstrating their persistence and potential for long range transport. More and more studies are continuing to examine the fate and transport of these flame retardant compounds in environmental samples and as such, reference materials are needed to provide quality control on these measurements. The National Institute of Standards and Technology (NIST) supports a national Standard Reference Material (SRM) program for measurement of organic contaminants such as PCBs, PAHs and chlorinated pesticides in environmental matrices. This current study was undertaken to provide reference measurements for PBDEs in selected SRMs that are currently used by various laboratories throughout the United States. These SRMs include matrices such as marine mammal blubber, lake trout tissue, mussel tissue, sediment, house dust and human serum. We report here reference values for 22 PBDE congeners that have been quantified in these seven types of SRMs.

  14. Procedure and reference standard to determine the structural resolution in coordinate metrology

    Science.gov (United States)

    Illemann, Jens; Bartscher, Markus; Jusko, Otto; Härtig, Frank; Neuschaefer-Rube, Ulrich; Wendt, Klaus

    2014-06-01

    A new procedure and reference standards for specifying the structural resolution in coordinate metrology traceable to the SI unit the metre are proposed. With the definition of the structural resolution, a significant gap will be closed to complete ‘acceptance and verification tests’ of the coordinate measuring systems (CMSs) which are specified in the ISO 10360 series dealing with tactile sensors, optical sensors, and x-ray computed tomography measurement systems (CTs). The proposed new procedure uses reference standards with circular rounded edges. The idea is to measure the radius of curvature on a calibrated round edge structure. From the deviation between the measured and the calibrated radius, an analogue Gaussian broadening of the measurement system is determined. This value is a well-defined and easy-to-apply measure to define the structural resolution for dimensional measurements. It is applicable to CMSs which are based on different sensing principles, e.g. tactile, optical and CT systems. On the other hand, it has a physical meaning similar to the classical optical point-spread function. It makes it possible to predict which smallest details the CMS is capable of measuring reliably for an arbitrary object shape. The theoretical background of the new procedure is given, an appropriate reference standard is described and comparative, quantitative measurement data of CMSs featuring different sensors are shown.

  15. Standard-Setting Methods as Measurement Processes

    Science.gov (United States)

    Nichols, Paul; Twing, Jon; Mueller, Canda D.; O'Malley, Kimberly

    2010-01-01

    Some writers in the measurement literature have been skeptical of the meaningfulness of achievement standards and described the standard-setting process as blatantly arbitrary. We argue that standard setting is more appropriately conceived of as a measurement process similar to student assessment. The construct being measured is the panelists'…

  16. Review of neutron activation analysis in the standardization and study of reference materials, including its application to radionuclide reference materials

    International Nuclear Information System (INIS)

    Byrne, A.R.

    1993-01-01

    Neutron activation analysis (NAA) plays a very important role in the certification of reference materials (RMs) and their characterization, including homogeneity testing. The features of the method are briefly reviewed, particularly aspects relating to its completely independent nuclear basis, its virtual freedom from blank problems, and its capacity for self-verification. This last aspect, arising from the essentially isotopic character of NAA, can be exploited by using different nuclear reactions and induced nuclides, and the possibility of employing two modes, one instrumental (nondestructive), the other radiochemical (destructive). This enables the derivation of essentially independent analytical information and the unique capacity of NAA for selfvalidation. The application of NAA to quantify natural or man-made radionuclides such as uranium, thorium, 237 Np, 129 I and 230 Th is discussed, including its advantages over conventional radiometric methods and its usefulness in providing independent data for nuclides where other confirmatory analyses are impossible, or are only recently becoming available through newer 'atom counting' techniques. Certain additional, prospective uses of NAA in the study of RMs and potential RMs are mentioned, including transmutation reactions, creation of endogenously radiolabelled matrices for production and study of RMs (such as dissolution and leaching tests, use as incorporated radiotracers for chemical recovery correction), and the possibility of molecular activation analysis for specification. (orig.)

  17. MATLAB Toolboxes for Reference Electrode Standardization Technique (REST) of Scalp EEG.

    Science.gov (United States)

    Dong, Li; Li, Fali; Liu, Qiang; Wen, Xin; Lai, Yongxiu; Xu, Peng; Yao, Dezhong

    2017-01-01

    Reference electrode standardization technique (REST) has been increasingly acknowledged and applied as a re-reference technique to transform an actual multi-channels recordings to approximately zero reference ones in electroencephalography/event-related potentials (EEG/ERPs) community around the world in recent years. However, a more easy-to-use toolbox for re-referencing scalp EEG data to zero reference is still lacking. Here, we have therefore developed two open-source MATLAB toolboxes for REST of scalp EEG. One version of REST is closely integrated into EEGLAB, which is a popular MATLAB toolbox for processing the EEG data; and another is a batch version to make it more convenient and efficient for experienced users. Both of them are designed to provide an easy-to-use for novice researchers and flexibility for experienced researchers. All versions of the REST toolboxes can be freely downloaded at http://www.neuro.uestc.edu.cn/rest/Down.html, and the detailed information including publications, comments and documents on REST can also be found from this website. An example of usage is given with comparative results of REST and average reference. We hope these user-friendly REST toolboxes could make the relatively novel technique of REST easier to study, especially for applications in various EEG studies.

  18. Development of a standard reference material containing 22 chlorinated hydrocarbon gases at 1 μmol/mol in nitrogen.

    Science.gov (United States)

    Li, Ning; Du, Jian; Yang, Jing; Fan, Qiang; Tian, Wen

    2017-11-01

    A gas standard mixture containing 22 chlorinated hydrocarbons in high purity nitrogen was prepared using a two-step weighing method and a gasifying apparatus developed in-house. The concentration of each component was determined using a gas chromatograph with flame ionization detection (GC/FID). Linear regression analysis of every component was performed using the gas standard mixture with concentrations ranging from 1 to 10 μmol/mol, showing the complete gasification of volatile organic compound (VOCs) species in a selected cylinder. Repeatability was also examined to ensure the reliability of the preparation method. In addition, no significant difference was observed between domestic treated and imported treated cylinders, which were conducive to reduction of the cost of raw materials. Moreover, the results of stability testing at different pressures and long-term stability tests indicated that the gas standard at 1 μmol/mol level with relative expanded uncertainties of 5% was stable above 2 MPa for a minimum of 12 months. Finally, a quantity comparison was conducted between the gas standard and a commercial gas standard from Scott Specialty Gases (now Air Liquide America Specialty Gases). The excellent agreement of every species suggested the favorable accuracy of our gas standard. Therefore, this reference material can be applied to routine observation of VOCs and for other purposes.

  19. Thermal Expansion and Density Data of UO2 and Simulated Fuel for Standard Reference

    International Nuclear Information System (INIS)

    Yang, Jae Hwan; Na, S. H.; Lee, J. W.; Kang, K. H.

    2010-01-01

    Standard Reference Data (SRD) is the scientific, technical data whose reliability and accuracy are evaluated by scientist group. Since SRD has a great impact on the improvement of national competitiveness by stirring up technological innovation in every sector of industries, many countries are making great efforts on establishing SRD in various areas. Data center for nuclear fuel material in Korea Atomic Energy Research Institute plays a role to providing property data of nuclear fuel material at high temperature, pressure, and radiation which are essential for the safety evaluation of nuclear power. In this study, standardization of data on thermal expansion and density of UO 2 were carried out in the temperature range from 300 K to 3100 K via uncertainty evaluation of indirectly produced data. Besides, standardization of data on thermal expansion and density of simulated fuel were also done in the temperature range from 350 K to 1750 K via uncertainty evaluation of directly produced data

  20. Marine Biotoxins: Occurrence, Toxicity, Regulatory Limits and Reference Methods

    Directory of Open Access Journals (Sweden)

    Pierina Visciano

    2016-07-01

    Full Text Available Harmful algal blooms are natural phenomena caused by the massive growth of phytoplankton that may contain highly toxic chemicals, the so-called marine biotoxins causing illness and even death to both aquatic organisms and humans. Their occurrence has been increased in frequency and severity, suggesting a worldwide public health risk. Marine biotoxins can accumulate in bivalve molluscs and regulatory limits have been set for some classes according to European Union legislation. These compounds can be distinguished in water- and fat-soluble molecules. The first group involves those of Paralytic Shellfish Poisoning and Amnesic Shellfish Poisoning, whereas the toxins soluble in fat can cause Diarrheic Shellfish Poisoning and Neurotoxic Shellfish Poisoning. Due to the lack of long-term toxicity studies, establishing tolerable daily intakes for any of these marine biotoxins was not possible, but an acute reference dose can be considered more appropriate, because these molecules show an acute toxicity. Dietary exposure assessment is linked both to the levels of marine biotoxins present in bivalve molluscs and the portion that could be eaten by consumers. Symptoms may vary from a severe gastrointestinal intoxication with diarrhea, nausea, vomiting, and abdominal cramps to neurological disorders such as ataxia, dizziness, partial paralysis, and respiratory distress. The official method for the detection of marine biotoxins is the mouse bioassay (MBA showing some limits due to ethical restrictions and insufficient specificity. For this reason, the liquid chromatography–mass spectrometry method has replaced MBA as the reference technique. However, the monitoring of algal blooms producing marine biotoxins should be regularly assessed in order to obtain more reliable, accurate estimates of bloom toxicity and their potential impacts.

  1. Cleanup standards and pathways analysis methods

    International Nuclear Information System (INIS)

    Devgun, J.S.

    1993-01-01

    Remediation of a radioactively contaminated site requires that certain regulatory criteria be met before the site can be released for unrestricted future use. Since the ultimate objective of remediation is to protect the public health and safety, residual radioactivity levels remaining at a site after cleanup must be below certain preset limits or meet acceptable dose or risk criteria. Release of a decontaminated site requires proof that the radiological data obtained from the site meet the regulatory criteria for such a release. Typically release criteria consist of a composite of acceptance limits that depend on the radionuclides, the media in which they are present, and federal and local regulations. In recent years, the US Department of Energy (DOE) has developed a pathways analysis model to determine site-specific soil activity concentration guidelines for radionuclides that do not have established generic acceptance limits. The DOE pathways analysis computer code (developed by Argonne National Laboratory for the DOE) is called RESRAD (Gilbert et al. 1989). Similar efforts have been initiated by the US Nuclear Regulatory Commission (NRC) to develop and use dose-related criteria based on genetic pathways analyses rather than simplistic numerical limits on residual radioactivity. The focus of this paper is radionuclide contaminated soil. Cleanup standards are reviewed, pathways analysis methods are described, and an example is presented in which RESRAD was used to derive cleanup guidelines

  2. 13 CFR 105.101 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... ethical conduct standards and financial disclosure regulations. 105.101 Section 105.101 Business Credit... RESPONSIBILITIES Standards of Conduct § 105.101 Cross-reference to employee ethical conduct standards and financial... to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635 and the...

  3. 18 CFR 3c.1 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-04-01

    ... employee ethical conduct standards and financial disclosure regulations. 3c.1 Section 3c.1 Conservation of... STANDARDS OF CONDUCT § 3c.1 Cross-reference to employee ethical conduct standards and financial disclosure... branch-wide financial disclosure regulations at 5 CFR part 2634, the Standards of Ethical Conduct for...

  4. The establishment of tocopherol reference intervals for Hungarian adult population using a validated HPLC method.

    Science.gov (United States)

    Veres, Gábor; Szpisjak, László; Bajtai, Attila; Siska, Andrea; Klivényi, Péter; Ilisz, István; Földesi, Imre; Vécsei, László; Zádori, Dénes

    2017-09-01

    Evidence suggests that decreased α-tocopherol (the most biologically active substance in the vitamin E group) level can cause neurological symptoms, most likely ataxia. The aim of the current study was to first provide reference intervals for serum tocopherols in the adult Hungarian population with appropriate sample size, recruiting healthy control subjects and neurological patients suffering from conditions without symptoms of ataxia, myopathy or cognitive deficiency. A validated HPLC method applying a diode array detector and rac-tocol as internal standard was utilized for that purpose. Furthermore, serum cholesterol levels were determined as well for data normalization. The calculated 2.5-97.5% reference intervals for α-, β/γ- and δ-tocopherols were 24.62-54.67, 0.81-3.69 and 0.29-1.07 μm, respectively, whereas the tocopherol/cholesterol ratios were 5.11-11.27, 0.14-0.72 and 0.06-0.22 μmol/mmol, respectively. The establishment of these reference intervals may improve the diagnostic accuracy of tocopherol measurements in certain neurological conditions with decreased tocopherol levels. Moreover, the current study draws special attention to the possible pitfalls in the complex process of the determination of reference intervals as well, including the selection of study population, the application of internal standard and method validation and the calculation of tocopherol/cholesterol ratios. Copyright © 2017 John Wiley & Sons, Ltd.

  5. GMOMETHODS: the European Union database of reference methods for GMO analysis.

    Science.gov (United States)

    Bonfini, Laura; Van den Bulcke, Marc H; Mazzara, Marco; Ben, Enrico; Patak, Alexandre

    2012-01-01

    In order to provide reliable and harmonized information on methods for GMO (genetically modified organism) analysis we have published a database called "GMOMETHODS" that supplies information on PCR assays validated according to the principles and requirements of ISO 5725 and/or the International Union of Pure and Applied Chemistry protocol. In addition, the database contains methods that have been verified by the European Union Reference Laboratory for Genetically Modified Food and Feed in the context of compliance with an European Union legislative act. The web application provides search capabilities to retrieve primers and probes sequence information on the available methods. It further supplies core data required by analytical labs to carry out GM tests and comprises information on the applied reference material and plasmid standards. The GMOMETHODS database currently contains 118 different PCR methods allowing identification of 51 single GM events and 18 taxon-specific genes in a sample. It also provides screening assays for detection of eight different genetic elements commonly used for the development of GMOs. The application is referred to by the Biosafety Clearing House, a global mechanism set up by the Cartagena Protocol on Biosafety to facilitate the exchange of information on Living Modified Organisms. The publication of the GMOMETHODS database can be considered an important step toward worldwide standardization and harmonization in GMO analysis.

  6. Austenitic chromium nickel steel as standard reference material in measurement of thermal and temperature conductivity

    International Nuclear Information System (INIS)

    Binkele, L.

    1990-01-01

    A niobium-stabilized CrNi steel with the NBS designation SRM 735 is introduced as WLF standard reference material in a report by Hust and Giarratano, for the temperature range 300-1200 K and for thermal conductivities around 20 W/mk. However, its specification does not show it to be a direct member of the DIN family of CrNi steels. This report should be regarded as a continuation and supplement to the above-mentioned efforts in America. On the one hand, a solution of a possibly too-narrow specification is aimed at for the reference material, where it is important how sensitive the thermal conductivity is to changes in the chemical composition and changes of the manufacturing parameters and what accuracy can be reached for the reference values with the best measurement techniques. On the other hand, the data base should be expanded and the accuracy of the reference curve should be improved if possible. (orig./MM) [de

  7. Cross-platform comparison of nucleic acid hybridization: toward quantitative reference standards.

    Science.gov (United States)

    Halvorsen, Ken; Agris, Paul F

    2014-11-15

    Measuring interactions between biological molecules is vitally important to both basic and applied research as well as development of pharmaceuticals. Although a wide and growing range of techniques is available to measure various kinetic and thermodynamic properties of interacting biomolecules, it can be difficult to compare data across techniques of different laboratories and personnel or even across different instruments using the same technique. Here we evaluate relevant biological interactions based on complementary DNA and RNA oligonucleotides that could be used as reference standards for many experimental systems. We measured thermodynamics of duplex formation using isothermal titration calorimetry, differential scanning calorimetry, and ultraviolet-visible (UV-vis) monitored denaturation/renaturation. These standards can be used to validate results, compare data from disparate techniques, act as a teaching tool for laboratory classes, or potentially to calibrate instruments. The RNA and DNA standards have many attractive features, including low cost, high purity, easily measurable concentrations, and minimal handling concerns, making them ideal for use as a reference material. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Diagnostic value of different adherence measures using electronic monitoring and virologic failure as reference standards.

    Science.gov (United States)

    Deschamps, Ann E; De Geest, Sabina; Vandamme, Anne-Mieke; Bobbaers, Herman; Peetermans, Willy E; Van Wijngaerden, Eric

    2008-09-01

    Nonadherence to antiretroviral therapy is a substantial problem in HIV and jeopardizes the success of treatment. Accurate measurement of nonadherence is therefore imperative for good clinical management but no gold standard has been agreed on yet. In a single-center prospective study nonadherence was assessed by electronic monitoring: percentage of doses missed and drug holidays and by three self reports: (1) a visual analogue scale (VAS): percentage of overall doses taken; (2) the Swiss HIV Cohort Study Adherence Questionnaire (SHCS-AQ): percentage of overall doses missed and drug holidays and (3) the European HIV Treatment Questionnaire (EHTQ): percentage of doses missed and drug holidays for each antiretroviral drug separately. Virologic failure prospectively assessed during 1 year, and electronic monitoring were used as reference standards. Using virologic failure as reference standard, the best results were for (1) the SHCS-AQ after electronic monitoring (sensitivity, 87.5%; specificity, 78.6%); (2) electronic monitoring (sensitivity, 75%; specificity, 85.6%), and (3) the VAS combined with the SHCS-AQ before electronic monitoring (sensitivity, 87.5%; specificity, 58.6%). The sensitivity of the complex EHTQ was less than 50%. Asking simple questions about doses taken or missed is more sensitive than complex questioning about each drug separately. Combining the VAS with the SHCS-AQ seems a feasible nonadherence measure for daily clinical practice. Self-reports perform better after electronic monitoring: their diagnostic value could be lower when given independently.

  9. Event-specific qualitative and quantitative detection of five genetically modified rice events using a single standard reference molecule.

    Science.gov (United States)

    Kim, Jae-Hwan; Park, Saet-Byul; Roh, Hyo-Jeong; Shin, Min-Ki; Moon, Gui-Im; Hong, Jin-Hwan; Kim, Hae-Yeong

    2017-07-01

    One novel standard reference plasmid, namely pUC-RICE5, was constructed as a positive control and calibrator for event-specific qualitative and quantitative detection of genetically modified (GM) rice (Bt63, Kemingdao1, Kefeng6, Kefeng8, and LLRice62). pUC-RICE5 contained fragments of a rice-specific endogenous reference gene (sucrose phosphate synthase) as well as the five GM rice events. An existing qualitative PCR assay approach was modified using pUC-RICE5 to create a quantitative method with limits of detection correlating to approximately 1-10 copies of rice haploid genomes. In this quantitative PCR assay, the square regression coefficients ranged from 0.993 to 1.000. The standard deviation and relative standard deviation values for repeatability ranged from 0.02 to 0.22 and 0.10% to 0.67%, respectively. The Ministry of Food and Drug Safety (Korea) validated the method and the results suggest it could be used routinely to identify five GM rice events. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Bias in the absorption coefficient determination of a fluorescent dye, standard reference material 1932 fluorescein solution

    International Nuclear Information System (INIS)

    DeRose, Paul C.; Kramer, Gary W.

    2005-01-01

    The absorption coefficient of standard reference material[registered] (SRM[registered]) 1932, fluorescein in a borate buffer solution (pH=9.5) has been determined at λ=488.0, 490.0, 490.5 and 491.0 nm using the US national reference UV/visible spectrophotometer. The purity of the fluorescein was determined to be 97.6% as part of the certification of SRM 1932. The solution measured was prepared gravimetrically by diluting SRM 1932 with additional borate buffer. The value of the absorption coefficient was corrected for bias due to fluorescence that reaches the detector and for dye purity. Bias due to fluorescence was found to be on the order of -1% for both monochromatic and polychromatic (e.g., diode-array based) spectrophotometers

  11. Age and gender leucocytes variances and references values generated using the standardized ONE-Study protocol

    DEFF Research Database (Denmark)

    Kverneland, Anders H.; Streitz, Mathias; Geissler, Edward

    2016-01-01

    blood flow cytometry. The performance of our protocols was challenged here by profiling samples from healthy volunteers to reveal age- and gender-dependent differences and to establish a standardized reference cohort for use in clinical trials. Whole blood samples from two different cohorts were...... analyzed (first cohort: n = 52, second cohort: n = 46, both 20–84 years with equal gender distribution). The second cohort was run as a validation cohort by a different operator. The “ONE Study” panels were applied to analyze expression of >30 different surface markers to enumerate proportional...... cohort. Thus, we have proven the utility of our strategy and generated reproducible reference ranges accounting for age- and gender-dependent differences, which are crucial for a better patient monitoring and individualized therapy....

  12. Standard reference material certification: contribution of NAA with a TRIGA reactor

    International Nuclear Information System (INIS)

    Orvini, E.; Speziali, M.; Salvini, A.; Herborg, C.

    2002-01-01

    Pavia has cooperative links with the major international agencies devoted to the certification of SRMs or CRMs as the Bureau Communautaire de Reference (BCR), the European Institute for Reference Materials and Measurement (IRMM), the USA National Institute of Standards and Technology (NIST) and the International Atomic Energy Agency (IAEA). During these cooperative works, a large amount of analytical data obtained with NAA has been compared, and meaningful methodological information achieved with respect to accuracy and precision in the analysis of several elements at different concentrations in various matrices. Analytical data on As, Cd, Cr, Co, Cu, Cs, Fe, Zn, K, Sc, U, Th, Al, Sb, Mn, V, Hg, Sr, Rb, Se,Pt, all the Rare Earths and halogens Br, Cl, I, have been obtained and contributed for the final certification

  13. Development and testing of standardized procedures and reference data for LWR surveillance

    International Nuclear Information System (INIS)

    McElroy, W.N.

    1979-02-01

    The resources and talents of many national and international organizations and laboratories, both governmental and industrial, are being used to establish analysis methods for predicting the embrittlement condition of light water reactor (LWR) primary systems. The exact interrelationships and responsibilities between those developing, understanding, combining, and applying state-of-the-art technology in dosimetry, metallurgy, and fracture mechanics for reactor systems analysis are being carefully reviewed and studied. This has resulted in a more comprehensive definition of the scope of new and updated ASTM standards required for the analysis and interpretation of LWR pressure vessel surveillance results. Fifteen new and updated ASTM standards have now been identified, together with a restructuring of the main interfaces between the individual standard practices, guides, and methods. The paper briefly discusses these standards and the initial results of multi-laboratory research work involved in their validation and calibration

  14. Characterization of standard reference material 2944, Bi-ion-doped glass, spectral correction standard for red fluorescence

    International Nuclear Information System (INIS)

    DeRose, Paul C.; Smith, Melody V.; Anderson, Jeffrey R.; Kramer, Gary W.

    2013-01-01

    Standard Reference Material (SRM) 2944 is a cuvette-shaped, Bi-ion-doped glass, recommended for optimal use for relative spectral correction of emission from 590 nm to 805 nm and day-to-day performance verification of steady-state fluorescence spectrometers. Properties of this standard that influence its effective use or contribute to the uncertainty in its certified emission spectrum were explored here. These properties include its photostability, absorbance, dissolution rate in water, anisotropy and temperature coefficient of fluorescence intensity. The expanded uncertainties (k=2) in the certified spectrum are about 4% around the nominal peak maximum at 704 nm and increase to about 6% at the wings, using an excitation wavelength of 515 nm. -- Highlights: ► The fluorescence emission spectrum of SRM 2944 was determined for spectral correction. ► This Bi-ion-doped glass has been certified in the fluorescence region from 530 nm to 830 nm. ► Fluorescence properties of the glass were determined, e.g., anisotropy, lifetime. ► SRM 2944 is photostable under common visible lamp excitation, when UV light is not present

  15. 29 CFR 2703.1 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Cross-reference to employee ethical conduct standards and...-reference to employee ethical conduct standards and financial disclosure regulations. Members and employees... of Ethical Conduct at 5 CFR part 2635; the Commission's regulations at 5 CFR part 8401, which...

  16. 12 CFR 264.101 - Cross-reference to employees' ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Cross-reference to employees' ethical conduct... § 264.101 Cross-reference to employees' ethical conduct standards and financial disclosure regulations... branch-wide standards of ethical conduct at 5 CFR part 2635 and the Board's regulation at 5 CFR part 6801...

  17. 12 CFR 336.1 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Cross-reference to employee ethical conduct... and Conduct § 336.1 Cross-reference to employee ethical conduct standards and financial disclosure... Branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Corporation regulation at 5 CFR part...

  18. 45 CFR 1105.1 - Cross-reference to employee ethical conduct standards and financial disclosure and financial...

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Cross-reference to employee ethical conduct... STANDARDS OF CONDUCT FOR EMPLOYEES § 1105.1 Cross-reference to employee ethical conduct standards and... ethical conduct at 5 CFR part 2635; the executive branch employees responsibilities and conduct...

  19. 49 CFR 99.735-1 - Cross-reference to ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Cross-reference to ethical conduct standards and... Transportation EMPLOYEE RESPONSIBILITIES AND CONDUCT General § 99.735-1 Cross-reference to ethical conduct... the executive branch-wide Standards of Ethical Conduct at 5 CFR part 2635, the Department of...

  20. 10 CFR 1010.102 - Cross-references to employee ethical conduct standards, financial disclosure regulations, and...

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Cross-references to employee ethical conduct standards... ENERGY (GENERAL PROVISIONS) CONDUCT OF EMPLOYEES § 1010.102 Cross-references to employee ethical conduct... Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR part 2635, the DOE regulation at...

  1. 22 CFR 705.101 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-reference to employee ethical conduct... INVESTMENT CORPORATION ADMINISTRATIVE PROVISIONS EMPLOYEE ETHICAL CONDUCT STANDARDS AND FINANCIAL DISCLOSURE REGULATIONS § 705.101 Cross-reference to employee ethical conduct standards and financial disclosure...

  2. 39 CFR 3000.735-101 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Cross-reference to employee ethical conduct... employee ethical conduct standards and financial disclosure regulations. Employees of the Postal Regulatory Commission (Commission) are subject and should refer to the executive branch-wide Standards of Ethical...

  3. 5 CFR 1300.1 - Cross-reference to employees ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Cross-reference to employees ethical conduct standards and financial disclosure regulations. 1300.1 Section 1300.1 Administrative Personnel OFFICE OF MANAGEMENT AND BUDGET ADMINISTRATIVE PROCEDURES STANDARDS OF CONDUCT § 1300.1 Cross-reference...

  4. 16 CFR 1030.101 - Cross-references to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... PRODUCT SAFETY COMMISSION GENERAL EMPLOYEE STANDARDS OF CONDUCT General § 1030.101 Cross-references to employee ethical conduct standards and financial disclosure regulations. Employees of the Consumer Product... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Cross-references to employee ethical conduct...

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

    Science.gov (United States)

    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.

  6. 22 CFR 1001.1 - Cross-references to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1001.1 Cross-references to employee ethical conduct... Foundation should refer to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...

  7. A method of camera calibration in the measurement process with reference mark for approaching observation space target

    Science.gov (United States)

    Zhang, Hua; Zeng, Luan

    2017-11-01

    Binocular stereoscopic vision can be used for space-based space targets near observation. In order to solve the problem that the traditional binocular vision system cannot work normally after interference, an online calibration method of binocular stereo measuring camera with self-reference is proposed. The method uses an auxiliary optical imaging device to insert the image of the standard reference object into the edge of the main optical path and image with the target on the same focal plane, which is equivalent to a standard reference in the binocular imaging optical system; When the position of the system and the imaging device parameters are disturbed, the image of the standard reference will change accordingly in the imaging plane, and the position of the standard reference object does not change. The camera's external parameters can be re-calibrated by the visual relationship of the standard reference object. The experimental results show that the maximum mean square error of the same object can be reduced from the original 72.88mm to 1.65mm when the right camera is deflected by 0.4 degrees and the left camera is high and low with 0.2° rotation. This method can realize the online calibration of binocular stereoscopic vision measurement system, which can effectively improve the anti - jamming ability of the system.

  8. A preliminary verification of the floating reference measurement method for non-invasive blood glucose sensing

    Science.gov (United States)

    Min, Xiaolin; Liu, Rong; Fu, Bo; Xu, Kexin

    2017-06-01

    In the non-invasive sensing of blood glucose by near-infrared diffuse reflectance spectroscopy, the spectrum is highly susceptible to the unstable and complicated background variations from the human body and the environment. In in vitro analyses, background variations are usually corrected by the spectrum of a standard reference sample that has similar optical properties to the analyte of interest. However, it is hard to find a standard sample for the in vivo measurement. Therefore, the floating reference measurement method is proposed to enable relative measurements in vivo, where the spectra under some special source-detector distance, defined as the floating reference position, are insensitive to the changes in glucose concentration due to the absorption effect and scattering effect. Because the diffuse reflectance signals at the floating reference positions only reflect the information on background variations during the measurement, they can be used as the internal reference. In this paper, the theoretical basis of the floating reference positions in a semi-infinite turbid medium was discussed based on the steady-state diffusion equation and its analytical solutions in a semi-infinite turbid medium (under the extrapolated boundary conditions). Then, Monte-Carlo (MC) simulations and in vitro experiments based on a custom-built continuous-moving spatially resolving double-fiber NIR measurement system, configured with two types of light source, a super luminescent diode (SLD) and a super-continuum laser, were carried out to verify the existence of the floating reference position in 5%, 10% and 20% Intralipid solutions. The results showed that the simulation values of the floating reference positions are close to the theoretical results, with a maximum deviation of approximately 0.3 mm in 1100-1320 nm. Great differences can be observed in 1340-1400 nm because the optical properties of Intralipid in this region don not satisfy the conditions of the steady

  9. Determination of technetium-99 in environmental standard reference materials by ICP-MS

    International Nuclear Information System (INIS)

    Tagami, K.; Uchida, S.

    2000-01-01

    Technetium-99 is an artificial radionuclide which is produced in the fission of 235 U or 239 Pu with a relatively high fission yield of ca. 6%. Because of its long half-life of 2.1 x 10 5 y, 99 Tc has been accumulating in the environment, and thus, is considered to present a potential risk for humans. It is important for dose assessments to identify the behavior of the nuclide in the environment. Analysis data of global fallout 99 Tc in environmental samples would give useful information for predicting the nuclide's behavior; however, due to its low concentration and analytical difficulties, not much data are available. Besides, no environmental standard reference material (SRM) for 99 Tc is available. If we could get suitable SRMs for 99 Tc analysis, it would be easier to determine the concentration of 99 Tc in environmental samples. The purpose of this study was to investigate the possibility of several SRMs to be used as references for low-level 99 Tc. For this, ICP-MS was used for 99 Tc determination. In recent years, ICP-MS has been used for 99 Tc measurements instead of radioactivity counting methods. The samples used were as follows: A) IAEA-373 (a grass sample collected on grassland near Chernobyl Nuclear Power Reactor, Ukraine), B) IAEA-375 (a soil sample collected on a field near Chernobyl Nuclear Power Reactor, Russia), C) IAEA-135 (a sea sediment sample affected by Sellafield, UK), D) five seaweed samples of which the concentration levels are different from each other (collected around the coast near Sellafield, UK). Throughout the chemical separation, 95m Tc was used as a yield monitor. The sample was incinerated for at least 2 h at 450degC. After 99 Tc extraction from the sample at 90degC for 3 h with 4M HNO 3 , the sample was filtered and the residue on the filter was washed with deionized water. The solution was diluted to ca. 0.1M HNO 3 then passed through TEVA resin column (EIChroM Industries, Inc.) to extract Tc onto the resin. Then Tc was

  10. Validation of IRDFF in 252Cf Standard and IRDF-2002 Reference Neutron Fields

    Directory of Open Access Journals (Sweden)

    Simakov Stanislav

    2016-01-01

    Full Text Available The results of validation of the latest release of International Reactor Dosimetry and Fusion File, IRDFF-1.03, in the standard 252Cf(s.f. and reference 235U(nth,f neutron benchmark fields are presented. The spectrum-averaged cross sections were shown to confirm IRDFF-1.03 in the 252Cf standard spontaneous fission spectrum; that was not the case for the current recommended spectra for 235U(nth,f. IRDFF was also validated in the spectra of the research reactor facilities ISNF, Sigma-Sigma and YAYOI, which are available in the IRDF-2002 collection. The ISNF facility was re-simulated to remove unphysical oscillations in the spectrum. IRDFF-1.03 was shown to reproduce reasonably well the spectrum-averaged data measured in these fields except for the case of YAYOI.

  11. IAEA nuclear data for applications: Cross section standards and the reference input parameter library (RIPL)

    International Nuclear Information System (INIS)

    Capote Noy, Roberto; Nichols, Alan L.; Pronyaev, Vladimir G.

    2003-01-01

    An integral part of the activities of the IAEA Nuclear Data Section involves the development of nuclear data for a wide range of user applications. When considering low-energy nuclear reactions induced by neutrons, photons and charged particles, a detailed knowledge is required of the production cross sections over a wide energy range, spectra of emitted particles and their angular distributions. Two highly relevant IAEA data development projects are considered in this paper. Neutron reaction cross-section standards represent the basic quantities needed in nuclear reaction cross-section measurements and evaluations. These standards and the covariance matrices of their uncertainties were previously evaluated and released in 1987. However, the derived uncertainties were subsequently considered to be unrealistic low due to the effect of the low uncertainties obtained in fitting the light element standards to the R-matrix model; as a result, evaluators were forced to scale up the uncertainties to 'expected values'. An IAEA Coordinated Research Project (CRP) entitled 'Improvement of the Standard Cross Sections for Light Elements' was initiated in 2002 to improve the evaluation methodology for the covariance matrix of uncertainty in the R-matrix model fits, and to produce R-matrix evaluations of the important light element standards. The scope of this CRP has been substantially extended to include the preparation of a full set of evaluated standard reactions and covariance matrices of their uncertainties. While almost all requests for nuclear data were originally addressed through measurement programmes, our theoretical understanding of nuclear phenomena has reached a reasonable degree of reliability and nuclear modeling has become standard practice in nuclear data evaluations (with measurements remaining crucial for data testing and benchmarking). Since nuclear model codes require a considerable amount of numerical input, the IAEA has instigated extensive efforts to

  12. Catalog of NBS standard reference materials, 1975--76 edition. Special pub

    International Nuclear Information System (INIS)

    Seward, R.W.

    1975-06-01

    This Catalog lists and describes the Standard Reference Materials (SRM's), Research Materials (RM's), and General Materials (GM's) currently distributed by the National Bureau of Standards, as well as many of the materials currently in preparation. SRM's are used to calibrate measurement systems and to provide a central basis for uniformity and accuracy of measurement. The unit and quantity, the type, and the certified characterization are listed for each SRM, as well as directions for ordering. The RM's are not certified, but are issued to meet the needs of scientists engaged in materials research. RM's are issued with a 'Report of Investigation', the sole authority of which is the author of the report. The GM's are standardized by some agency other than NBS. NBS acts only as a distribution point and does not participate in the standardization of these materials. Announcements of new and renewal SRM's, RM's and GM's are made in the semi-annual supplements of this Catalog, SRM Price List, and in scientific and trade journals

  13. New reference materials improvement of methods of measurements

    International Nuclear Information System (INIS)

    Marchandise, H.

    1985-01-01

    The report summarizes the development of about 120 reference materials in a variety of fields (non ferrous metals, trace element analysis, food products, biomedical analysis, physical and technical properties of solid materials). The document also provides practical advice for trace element analyses, describes the principles followed for certifying reference materials and provides recommendations for their use

  14. Standardization of reference radiation field of beta for 85Kr using extrapolation chamber

    International Nuclear Information System (INIS)

    Nazaroh; Fendinugroho

    2013-01-01

    Standardization of reference radiation field of beta for 85 Kr in PTKMR-BATAN Laboratory has been performed at the SDD's 30 cm by using extrapolation chamber detector, coupled with Uni dose electrometer. The result was : (8.98±3 %) mGy/h, at 95 % confidence level. The aim of standardization of reference radiation field is to support radiation protection and safety program, provided by the International Atomic Energy Agency to its Member States, included BATAN-Indonesia, especially, PTKMR. The aim of radiation protection program and safety program is to promote an internationally harmonized approach for radiation measurement in protection level, besides for calibration of radiation measuring instrument, which users spread across Indonesia, with the number of about 795 firms in the year of 2012. These benefits can be felt by workers, communities and the environment, because by calibration, measurement survey meter, pocket dosimeter and TLD to be more accurate so that the radiation dose received by radiation workers is accurate and can be ascertained in a specified period, not to exceed a predetermined NBD by BAPETEN. The aim of this calibration is appropriate with the primary objective of calibration on IAEA/TRS16:2000. (author)

  15. Standardization of methods of maxillofacial roentgenology

    International Nuclear Information System (INIS)

    Rabukhina, N.A.; Arzhantsev, A.P.; Chikirdin, Eh.G.; Tombak, M.I.; Stavitskij, R.V.; Vasil'ev, Yu.D.

    1989-01-01

    Typical errors in teeth roentgenography reproduced in experiment, indicate that considerable disproportional distortions of images of anatomical structures which are decisive for radiodiagnosis, may occur in these cases. Standardization of intraoral roentgenography is based on a strict position of the patient's head, angle of inclination and alignment of a tube. Specialized R3-1 film should be used

  16. Validity Study of a Jump Mat Compared to the Reference Standard Force Plate.

    Science.gov (United States)

    Rogan, Slavko; Radlinger, Lorenz; Imhasly, Caroline; Kneubuehler, Andrea; Hilfiker, Roger

    2015-12-01

    In the field of vertical jump diagnostics, force plates (FP) are the reference standard. Recently, despite a lack of evidence, jump mats have been used increasingly. Important factors in favor of jumping mats are their low cost and portability. This validity study compared the Haynl-Elektronik jump mat (HE jump mat) with the reference standard force plate. Ten healthy volunteers participated and each participant completed three series of five drop jumps (DJ). The parameters ground contact time (GCT) and vertical jump height (VJH) from the HE jump mat and the FP were used to evaluate the concurrent validity. The following statistical calculations were performed: Pearson's correlation (r), Bland-Altman plots (standard and for adjusted trend), and regression equations. The Bland-Altman plots suggest that the HE jump mat measures shorter contact times and higher jump heights than the FP. The trend-adjusted Bland-Altman plot shows higher mean differences and wider wing-spreads of confidence limits during longer GCT. During the VJH the mean differences and the wing-spreads of the confidence limits throughout the range present as relatively constant. The following regression equations were created, as close as possible to the true value: GCT = 5.920385 + 1.072293 × [value HE jump mat] and VJH = -1.73777 + 1.011156 × [value HE jump mat]. The HE jump mat can be recommended in relation to the validity of constraints. In this study, only a part of the quality criteria were examined. For the final recommendation it is advised to examine the HE jump mat on the other quality criteria (test-retest reliability, sensitivity change).

  17. 41 CFR 105-735.1 - Cross-references to employee ethical conduct standards, financial disclosure regulations, and...

    Science.gov (United States)

    2010-07-01

    ... employee ethical conduct standards, financial disclosure regulations, and other regulations. 105-735.1... CONDUCT § 105-735.1 Cross-references to employee ethical conduct standards, financial disclosure... executive branch-wide standards of ethical conduct at 5 CFR part 2635, GSA's regulations at 5 CFR part 6701...

  18. 36 CFR 400.1 - Cross-references to employees' ethical conduct standards, financial disclosure regulations and...

    Science.gov (United States)

    2010-07-01

    ...' ethical conduct standards, financial disclosure regulations and other conduct rules. 400.1 Section 400.1... CONDUCT § 400.1 Cross-references to employees' ethical conduct standards, financial disclosure regulations... executive branch-wide standards of ethical conduct and financial disclosure regulations at 5 CFR parts 2634...

  19. 29 CFR 1600.101 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 4 2010-07-01 2010-07-01 false Cross-reference to employee ethical conduct standards and... to employee ethical conduct standards and financial disclosure regulations. Employees of the Equal Employment Opportunity Commission (EEOC) are subject to the executive branch-wide Standards of Ethical...

  20. 36 CFR 811.1 - Cross-references to employees' ethical conduct standards, financial disclosure and financial...

    Science.gov (United States)

    2010-07-01

    ...' ethical conduct standards, financial disclosure and financial interests regulations and other conduct... EMPLOYEE RESPONSIBILITIES AND CONDUCT § 811.1 Cross-references to employees' ethical conduct standards... Council on Historic Preservation are subject to the executive branch-wide standards of ethical conduct...

  1. 24 CFR 0.1 - Cross-reference to employees ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-04-01

    ... ethical conduct standards and financial disclosure regulations. 0.1 Section 0.1 Housing and Urban... Cross-reference to employees ethical conduct standards and financial disclosure regulations. Employees...-wide standards of ethical conduct at 5 CFR part 2635, the Department's regulation at 5 CFR part 7501...

  2. Biomass-burning derived aromatic acids in NIST standard reference material 1649b and the environmental implications

    Science.gov (United States)

    Gao, Shaopeng; Xu, Baiqing; Dong, Xueling; Zheng, Xiaoyan; Wan, Xin; Kang, Shichang; Song, Qiuyin; Kawamura, Kimitaka; Cong, Zhiyuan

    2018-07-01

    Biomass burning is a serious problem in the environment and climate system. However, the source identification of biomass-burning aerosols was somewhat impeded, partly due to the difficulty in quantification of relevant molecular markers. In this study, we present reference values for five aromatic acids (including p-hydroxybenzoic, vanillic, dehydroabietic, syringic and p-coumaric acids) in the NIST Standard Reference Material (SRM) 1649b. The concentration of levoglucosan was also revisited. Notable positive matrix effect was found for vanillic, dehydroabietic, syringic and coumaric acid. Using the standard addition method, the average value of p-hydroxybenzoic, vanillic, syringic, dehydroabietic and p-coumaric acids in SRM 1649b were found to be 26.9, 9.53, 1.13, 7.60 and 1.66 μg g-1, respectively. The analytical method developed in this study was also applied to the PM10 samples from Beijing and PM2.5 samples from South Asia (Godavari, Nepal). The ratios of vanillic to p-hydroxybenzoic acid and syringic to vanillic acid further suggested that their biomass-burning types are mainly related to hard wood and herbaceous species (i.e., agricultural residues).

  3. Antibody reactions methods in safety standards

    International Nuclear Information System (INIS)

    Shubik, V.M.; Sirasdinov, V.G.; Zasedatelev, A.A.; Kal'nitskij, S.A.; Livshits, R.E.

    1978-01-01

    Results of determinations are presented of autoantibodies in white rats to which the radionuclides 137 Cs, 226 Ra, and 90 Sr that show different distribution patterns in the body, have been administered chronically. Autoantiboby production is found to increase when the absorbed doses are close to or exceeding seven- to tenfold the maximum permissible values. The results obtained point to the desirability of autoantibody determination in studies aimed at setting hygienic standards for the absorption of radioactive substances

  4. The Kjeldahl method as a primary reference procedure for total protein in certified reference materials used in clinical chemistry. I. A review of Kjeldahl methods adopted by laboratory medicine.

    Science.gov (United States)

    Chromý, Vratislav; Vinklárková, Bára; Šprongl, Luděk; Bittová, Miroslava

    2015-01-01

    We found previously that albumin-calibrated total protein in certified reference materials causes unacceptable positive bias in analysis of human sera. The simplest way to cure this defect is the use of human-based serum/plasma standards calibrated by the Kjeldahl method. Such standards, commutative with serum samples, will compensate for bias caused by lipids and bilirubin in most human sera. To find a suitable primary reference procedure for total protein in reference materials, we reviewed Kjeldahl methods adopted by laboratory medicine. We found two methods recommended for total protein in human samples: an indirect analysis based on total Kjeldahl nitrogen corrected for its nonprotein nitrogen and a direct analysis made on isolated protein precipitates. The methods found will be assessed in a subsequent article.

  5. Miscellaneous standard methods for Apis mellifera research

    DEFF Research Database (Denmark)

    Human, Hannelie; Brodschneider, Robert; Dietemann, Vincent

    2013-01-01

    A variety of methods are used in honey bee research and differ depending on the level at which the research is conducted. On an individual level, the handling of individual honey bees, including the queen, larvae and pupae are required. There are different methods for the immobilising, killing an...

  6. Development of a quality assured calibration method for the PSI radon chamber reference atmosphere

    International Nuclear Information System (INIS)

    Schuler, C.; Butterweck-Dempewolf, G.; Vezzu, G.

    1997-01-01

    Radon detectors and measuring instruments are calibrated at the PSI Reference Laboratory for Radon Gas Concentration Measurements by exposing them to a calibrated radon reference atmosphere in the PSI radon chamber. A sophisticated and quality assured calibration technique was developed which guarantees the traceability of this radon chamber reference atmosphere to standards of internationally acknowledged primary laboratories. (author) 2 figs., 2 refs

  7. Performance of different methods for reference evapotranspiration estimation in Jaíba, Brazil

    Directory of Open Access Journals (Sweden)

    Gustavo H. da Silva

    Full Text Available ABSTRACT FAO Penman-Monteith (FO-PM is considered the standard method for the estimation of reference evapotranspiration (ET0 but requires various meteorological data, which are often not available. The objective of this work was to evaluate the performance of the FAO-PM method with limited meteorological data and other methods as alternatives to estimate ET0 in Jaíba-MG. The study used daily meteorological data from 2007 to 2016 of the National Institute of Meteorology’s station. Daily ET0 values were randomized, and 70% of these were used to determine the calibration parameters of the ET0 for the equations of each method under study. The remaining data were used to test the calibration against the standard method. Performance evaluation was based on Willmott’s index of agreement, confidence coefficient and root-mean-square error. When one meteorological variable was missing, either solar radiation, relative air humidity or wind speed, or in the simultaneous absence of wind speed and relative air humidity, the FAO-PM method showed the best performances and, therefore, was recommended for Jaíba. The FAO-PM method with two missing variables, one of them being solar radiation, showed intermediate performance. Methods that used only air temperature data are not recommended for the region.

  8. Rare earths analysis of rock samples by instrumental neutron activation analysis, internal standard method

    International Nuclear Information System (INIS)

    Silachyov, I.

    2016-01-01

    The application of instrumental neutron activation analysis for the determination of long-lived rare earth elements (REE) in rock samples is considered in this work. Two different methods are statistically compared: the well established external standard method carried out using standard reference materials, and the internal standard method (ISM), using Fe, determined through X-ray fluorescence analysis, as an element-comparator. The ISM proved to be the more precise method for a wide range of REE contents and can be recommended for routine practice. (author)

  9. Preparation and certification of trace mercury in water standard reference materials

    International Nuclear Information System (INIS)

    Moody, J.R.; Paulsen, P.J.; Rains, T.C.; Rook, H.L.

    1976-01-01

    The study of mercury in natural water supplies requires a Standard Reference Material (SRM) with a certified concentration at the 1 ng/g level. NBS SRM's have been prepared with nominal mercury concentrations of 1.5 μg/g and 1.2 ng/g. Confirmation of these values was obtained by neutron activation, atomic absorption, and isotope dilution-spark source mass spectrometry (IDSSMS). Nitric acid and trace amounts of gold were added to achieve a stable mercury concentration. The precautions observed for cleaning the glass and Teflon containers, preparation of mercury solutions, and the packaging of the SRM's are given. As an example of the care needed in the analysis of mercury at these levels, specific details are presented for the chemistry required to prepare samples for the spark source mass spectrometer

  10. Crystal structure of isopropyl 2-hydroxy-2-phenylacetate: a pharmacopoeia reference standard

    Directory of Open Access Journals (Sweden)

    Ivan Isaiev

    2017-05-01

    Full Text Available The title compound, C11H14O3, is used as a pharmacopoeia reference standard for determining impurities in the drug Pregabalin, used for the treatment of epilepsy and diabetic neuropathic pain. The molecule is far from being planar, with the dihedral angle between the planes of the aromatic ring and the carboxyl fragment (O—C=O being 76.1 (6°. The isopropyl substituent is located in a synperiplanar position relative to the C=O bond and is turned so that the C—O—C—H torsion angle is −43.7°. In the crystal, bifurcated O—H...(O,O hydrogen bonds, enclosing R12(5 ring motifs, lead to the formation of chains propagating along the c-axis direction. Inversion-related chains are linked by the C—H...O hydrogen bonds, forming undulating layers lying parallel to the bc plane.

  11. Tentative reference method for measurement of tritium in environmental waters. Environmental monitoring series

    International Nuclear Information System (INIS)

    1975-12-01

    A tentative reference method for the measurement of tritium in potable and nonpotable environmental water is described. Water samples are treated with sodium hydroxide and potassium permanganate and then a water fraction is separated from interferences by distillation. Two distillation procedures are described, a simple aqueous distillation for samples from potable water sources, and an aqueous-azeotropic-benzene distillation for nonpotable water sources. Alliquots of a designated distillate fraction are measured for tritium activity by liquid scintillation detection. Distillation recovery and counting efficiency factors are determined with tritium standards. Results are reported in picocuries per milliliter

  12. Standardized Methods for Detection of Poliovirus Antibodies.

    Science.gov (United States)

    Weldon, William C; Oberste, M Steven; Pallansch, Mark A

    2016-01-01

    Testing for neutralizing antibodies against polioviruses has been an established gold standard for assessing individual protection from disease, population immunity, vaccine efficacy studies, and other vaccine clinical trials. Detecting poliovirus specific IgM and IgA in sera and mucosal specimens has been proposed for evaluating the status of population mucosal immunity. More recently, there has been a renewed interest in using dried blood spot cards as a medium for sample collection to enhance surveillance of poliovirus immunity. Here, we describe the modified poliovirus microneutralization assay, poliovirus capture IgM and IgA ELISA assays, and dried blood spot polio serology procedures for the detection of antibodies against poliovirus serotypes 1, 2, and 3.

  13. The Organic Food Method and Movement: An Interdisciplinary Reference Review

    Science.gov (United States)

    Park, Elizabeth E.

    2011-01-01

    From popular movies to New York Times bestsellers, organic food is widely acknowledged to be of growing importance. Many community college students are asking: How is organic food different from everything else in the grocery store? What impact does farming have on the environment? How safe is our food? A survey of reference works introduces…

  14. Establishing Upper Limits for Item Ratings for the Angoff Method: Are Resulting Standards More 'Realistic'?

    Science.gov (United States)

    Reid, Jerry B.

    This report investigates an area of uncertainty in using the Angoff method for setting standards, namely whether or not a judge's conceptualizations of borderline group performance are realistic. Ratings are usually made with reference to the performance of this hypothetical group, therefore the Angoff method's success is dependent on this point.…

  15. Determination of caffeine, theobromine, and theophylline in standard reference material 2384, baking chocolate, using reversed-phase liquid chromatography.

    Science.gov (United States)

    Thomas, Jeanice Brown; Yen, James H; Schantz, Michele M; Porter, Barbara J; Sharpless, Katherine E

    2004-06-02

    A rapid and selective isocratic reversed-phase liquid chromatographic method has been developed at the National Institute of Standards and Technology to simultaneously measure caffeine, theobromine, and theophylline in a food-matrix standard reference material (SRM) 2384, Baking Chocolate. The method uses isocratic elution with a mobile phase composition (volume fractions) of 10% acetronitrile/90% water (pH adjusted to 2.5 using acetic acid) at a flow rate of 1.5 mL/min with ultraviolet absorbance detection (274 nm). Total elution time for these analytes is less than 15 min. Concentration levels of caffeine, theobromine, and theophylline were measured in single 1-g samples taken from each of eight bars of chocolate over an eight-day period. Samples were defatted with hexane, and beta-hydroxyethyltheophylline was added as the internal standard. The repeatability for the caffeine, theobromine, and theophylline measurements was 5.1, 2.3, and 1.9%, respectively. The limit of quantitation for all analytes was theobromine, and theophylline in SRM 2384.

  16. The use of high accuracy NAA for the certification of NIST Standard Reference Materials

    International Nuclear Information System (INIS)

    Becker, D.A.; Greenberg, R.R.; Stone, S.

    1991-01-01

    Neutron activation analysis (NAA) is only one of many analytical techniques used at the National Institute of Standards and Technology (NIST) for the certification of NIST Standard Reference Materials (SRMs). We compete daily against all of the other available analytical techniques in terms of accuracy, precision, and the cost required to obtain that requisite accuracy and precision. Over the years, the authors have found that NAA can and does compete favorably with these other techniques because of its' unique capabilities for redundancy and quality assurance. Good examples are the two new NIST leaf SRMs, Apple Leaves (SRM 1515) and Peach Leaves (SRM 1547). INAA was used to measure the homogeneity of 12 elements in 15 samples of each material at the 100 mg sample size. In addition, instrumental and radiochemical NAA combined for 27 elemental determinations, out of a total of 54 elemental determinations made on each material with all NIST techniques combined. This paper describes the NIST NAA procedures used in these analyses, the quality assurance techniques employed, and the analytical results for the 24 elements determined by NAA in these new botanical SRMs. The NAA results are also compared to the final certified values for these SRMs

  17. Determination of 25 elements in biological standard reference materials by neutron activation analysis

    International Nuclear Information System (INIS)

    Guzzi, G.; Pietra, R.; Sabbioni, E.

    1974-12-01

    Standard and Certified Reference Materials programme of the JRC includes the determination of trace elements in complex biological samples delivered by the U.S. National Bureau of Standards: Bovine liver (NBS SRM 1577), Orchard Leaves (NBS SRM 1571) and Tomato Leaves. The study has been performed by the use of neutron activation analysis. Due to the very low concentration of some elements, radiochemical groups or elemental separation procedures were necessary. The paper describes the techniques used to analyse 25 elements. Computer assisted instrumental neutron activation analysis with high resolution Ge(Li) spectrometry was considerably advantageous in the determination of Na, K, Cl, Mn, Fe, Rb and Co and in some cases of Ca, Zn, Cs, Sc, and Cr. For low contents of Ca, Mg, Ni and Si special chemical separation schemes, followed by Cerenkov counting have been developped. Two other separation procedures allowing the determination of As, Cd, Ga, Hg, Mo, Cu, Sr Se, Ba and P have been set up. The first, the simplified one involves the use of high resolution Ge(Li) detectors, the second, the more complete one involves a larger number of shorter measurements performed by simpler and more sensitive techniques, such as NaI(Tl) scintillation spectrometry and Cerenkov counting. The results obtained are presented and discussed

  18. Implementation of Dietary Reference Intake Standards in Preschool Menus in Poland.

    Science.gov (United States)

    Myszkowska-Ryciak, Joanna; Harton, Anna

    2018-05-10

    Although the nutritional value of preschool menus largely determines the proper nutrition of attending children, their nutrient composition often does not meet the standards. The purpose of the study was to assess the nutritional value of menus served in preschools throughout Poland. We analyzed a sample of 10 daily menus and inventory reports reflecting foods and beverages served in 270 full-board government-sponsored preschools. Nutrient content was calculated per child per day, and compared with 70% of dietary reference intake (DRI) for children aged 1⁻3 and 4⁻6. The content of energy, protein, fat, and carbohydrates generally exceeded 70% of DRI. The amount of vitamins was correct, with the exception of vitamin D (100% of daycare centers (DCCs) were below the recommendations); in ≤3% of preschools vitamin E, folate, and niacin were below DRI. Calcium was too low in 63% of preschools for children aged 1⁻3 years and in 99% for 4⁻6-year-olds. A shortage of iodine, iron, and potassium (especially for 4⁻6-year-olds) was observed in a small number of preschools. Our study highlights the need for uniform legal standards of nutrition in childcare centers, based on the current recommendations for the age group.

  19. New reference charts for testicular volume in Dutch children and adolescents allow the calculation of standard deviation scores.

    Science.gov (United States)

    Joustra, Sjoerd D; van der Plas, Evelyn M; Goede, Joery; Oostdijk, Wilma; Delemarre-van de Waal, Henriette A; Hack, Wilfried W M; van Buuren, Stef; Wit, Jan M

    2015-06-01

    Accurate calculations of testicular volume standard deviation (SD) scores are not currently available. We constructed LMS-smoothed age-reference charts for testicular volume in healthy boys. The LMS method was used to calculate reference data, based on testicular volumes from ultrasonography and Prader orchidometer of 769 healthy Dutch boys aged 6 months to 19 years. We also explored the association between testicular growth and pubic hair development, and data were compared to orchidometric testicular volumes from the 1997 Dutch nationwide growth study. The LMS-smoothed reference charts showed that no revision of the definition of normal onset of male puberty - from nine to 14 years of age - was warranted. In healthy boys, the pubic hair stage SD scores corresponded with testicular volume SD scores (r = 0.394). However, testes were relatively small for pubic hair stage in Klinefelter's syndrome and relatively large in immunoglobulin superfamily member 1 deficiency syndrome. The age-corrected SD scores for testicular volume will aid in the diagnosis and follow-up of abnormalities in the timing and progression of male puberty and in research evaluations. The SD scores can be compared with pubic hair SD scores to identify discrepancies between cell functions that result in relative microorchidism or macroorchidism. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  20. 12 CFR 1401.1 - Cross-references to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Cross-references to employee ethical conduct... INSURANCE CORPORATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1401.1 Cross-references to employee ethical... the Farm Credit System Insurance Corporation are subject to the Standards of Ethical Conduct for...

  1. 22 CFR 1504.1 - Cross-references to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-references to employee ethical conduct... FOUNDATION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1504.1 Cross-references to employee ethical conduct... Foundation are subject to the Standards of Ethical Conduct for Employees of the Executive Branch at 5 CFR...

  2. 22 CFR 1100.1 - Cross-references to employee ethical conduct standards, financial disclosure and financial...

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Cross-references to employee ethical conduct... STATES SECTION EMPLOYEE RESPONSIBILITIES AND CONDUCT § 1100.1 Cross-references to employee ethical... executive branch standards of ethical conduct contained in 5 CFR part 2635, the executive branch financial...

  3. 12 CFR 400.101 - Cross-reference to employee financial disclosure and ethical conduct standards regulations.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Cross-reference to employee financial disclosure and ethical conduct standards regulations. 400.101 Section 400.101 Banks and Banking EXPORT-IMPORT.... Employees of the Export-Import Bank of the United States (Bank) should refer to: (a) The executive branch...

  4. 45 CFR 706.1 - Cross-references to employee ethical conduct standards, financial disclosure and financial...

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Cross-references to employee ethical conduct... 706.1 Public Welfare Regulations Relating to Public Welfare (Continued) COMMISSION ON CIVIL RIGHTS EMPLOYEE RESPONSIBILITIES AND CONDUCT § 706.1 Cross-references to employee ethical conduct standards...

  5. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa

    Directory of Open Access Journals (Sweden)

    Irith De Baetselier

    2016-10-01

    Full Text Available Background: Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs. Verification of CRRs is time consuming and often requires a statistical background. Objectives: We report on an easy and cost-saving method to verify CRRs. Methods: Using a former method introduced by Sigma Diagnostics, three study sites in sub- Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants. Results: Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected. Conclusion: To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory.

  6. Standardization of 57Co using different methods of LNMRI

    International Nuclear Information System (INIS)

    Rezende, E.A.; Lopes, R.T.; Silva, C.J. da; Poledna, R.; Silva, R.L. da; Tauhata, L.

    2015-01-01

    The activity of a 57 Co solution was determined using four LNMRI different measurement methods. The solution was standardized by live-timed anti-coincidence method and sum-peak method. The efficiency curve and standard-sample comparison methods were also used in this comparison. The results and their measurement uncertainties demonstrating the equivalence of these methods. As an additional contribution, the gamma emission probabilities of 57 Co were also determined. (author)

  7. 77 FR 202 - Federal Acquisition Regulation; Updated Financial Accounting Standards Board Accounting References

    Science.gov (United States)

    2012-01-03

    ... 9000-AM00 Federal Acquisition Regulation; Updated Financial Accounting Standards Board Accounting... accounting standards owing to the Financial Accounting Standards Board's Accounting Standards Codification of Generally Accepted Accounting Principles. DATES: Effective Date: February 2, 2012. FOR FURTHER INFORMATION...

  8. Reference Values for Spirometry Derived Using Lambda, Mu, Sigma (LMS) Method in Korean Adults: in Comparison with Previous References.

    Science.gov (United States)

    Jo, Bum Seak; Myong, Jun Pyo; Rhee, Chin Kook; Yoon, Hyoung Kyu; Koo, Jung Wan; Kim, Hyoung Ryoul

    2018-01-15

    The present study aimed to update the prediction equations for spirometry and their lower limits of normal (LLN) by using the lambda, mu, sigma (LMS) method and to compare the outcomes with the values of previous spirometric reference equations. Spirometric data of 10,249 healthy non-smokers (8,776 females) were extracted from the fourth and fifth versions of the Korea National Health and Nutrition Examination Survey (KNHANES IV, 2007-2009; V, 2010-2012). Reference equations were derived using the LMS method which allows modeling skewness (lambda [L]), mean (mu [M]), and coefficient of variation (sigma [S]). The outcome equations were compared with previous reference values. Prediction equations were presented in the following form: predicted value = e{a + b × ln(height) + c × ln(age) + M - spline}. The new predicted values for spirometry and their LLN derived using the LMS method were shown to more accurately reflect transitions in pulmonary function in young adults than previous prediction equations derived using conventional regression analysis in 2013. There were partial discrepancies between the new reference values and the reference values from the Global Lung Function Initiative in 2012. The results should be interpreted with caution for young adults and elderly males, particularly in terms of the LLN for forced expiratory volume in one second/forced vital capacity in elderly males. Serial spirometry follow-up, together with correlations with other clinical findings, should be emphasized in evaluating the pulmonary function of individuals. Future studies are needed to improve the accuracy of reference data and to develop continuous reference values for spirometry across all ages. © 2018 The Korean Academy of Medical Sciences.

  9. Standard methods for analysis of phosphorus-32

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Methods are described for the determination of the radiochemical purity and the absolute disintegration rate of 32 P radioisotope preparations. The 32 P activity is determined by β counting, and other low-energy β radioactive contaminants are determined by aluminum-absorption curve data. Any γ-radioactive contaminants are determined by γ counting. Routine chemical testing is used to establish the chemical characteristics. The presence or absence of heavy metals is established by spot tests; free acid is determined by use of a pH meter; total solids are determined gravimetrically by evaporation and ignition at a temperature sufficient to evaporate the mineral acids, HCl and HNO 3 ; and nonvolatile matter, defined as that material which does not evaporate or ignite at a temperature sufficient to convert C to CO or CO 2 , is determined gravimetrically after such ignition

  10. Determination of platinum-group elements in the geological standard reference materials by isotope dilution-ICPMS

    Energy Technology Data Exchange (ETDEWEB)

    Mingyue, Hu; Hongliao, He [National Research Center for Geoanalysis, Beijing (China)

    2005-10-15

    Platinum group elements (PGEs) includes platinum, palladium, iridium, osmium, rhodium and ruthenium. It has very high economic and scientific value in the field of geoscience and environmental science. But the analysis data referred by the different lab are very disperse because of the difficulty of the determination of PGEs. It makes very difficult to fix the value of the PGEs in the standard reference materials. In the article, the values of the PGEs in the standard reference materials of ocean sediment are determined by isotope dilution technique and dependable values of these elements are provided. (authors)

  11. Determination of platinum-group elements in the geological standard reference materials by isotope dilution-ICPMS

    International Nuclear Information System (INIS)

    Hu Mingyue; He Hongliao

    2005-01-01

    Platinum group elements (PGEs) includes platinum, palladium, iridium, osmium, rhodium and ruthenium. It has very high economic and scientific value in the field of geoscience and environmental science. But the analysis data referred by the different lab are very disperse because of the difficulty of the determination of PGEs. It makes very difficult to fix the value of the PGEs in the standard reference materials. In the article, the values of the PGEs in the standard reference materials of ocean sediment are determined by isotope dilution technique and dependable values of these elements are provided. (authors)

  12. Standard reference radiographs for steel castings up to 2 in. (50.8 mm) in thickness

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice describes accepted procedures for and factors that influence laboratory immersion corrosion tests, particularly mass loss tests. These factors include specimen preparation, apparatus, test conditions, methods of cleaning specimens, evaluation of results, and calculation and reporting of corrosion rates. This practice also emphasizes the importance of recording all pertinent data and provides a checklist for reporting test data. Other ASTM procedures for laboratory corrosion tests are tabulated in the Appendix. (Warning-In many cases the corrosion product on the reactive metals titanium and zirconium is a hard and tightly bonded oxide that defies removal by chemical or ordinary mechanical means. In many such cases, corrosion rates are established by mass gain rather than mass loss.) 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. This standard does not purport to address all of the safety concerns, if any, assoc...

  13. Method of using a nuclear magnetic resonance spectroscopy standard

    Science.gov (United States)

    Spicer, Leonard D.; Bennett, Dennis W.; Davis, Jon F.

    1985-01-01

    (CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy, wherein the resonance peaks of either .sup.1 H, .sup.13 C, .sup.15 N, or .sup.29 Si may be used as a reference.

  14. Reference standard of penile size and prevalence of buried penis in Japanese newborn male infants.

    Science.gov (United States)

    Matsuo, Nobutake; Ishii, Tomohiro; Takayama, John I; Miwa, Masayuki; Hasegawa, Tomonobu

    2014-01-01

    The present study set forth the reference values for penile size and determined the prevalence of buried penis in Japanese full-term newborns. The stretched penile length was measured and the presence of buried penis was assessed at 1-7 days of age in 547 Japanese full-term newborn infants born between 2008 and 2012 in Tokyo. The stretched penile lengths were compared at 1-12 hours and 1-7 days of age in 63 infants and by two observers in 73 infants to estimate postnatal changes and interobserver variation, respectively. The mean stretched penile length was 3.06 cm (SD, 0.26; 95% confidence interval [CI], 3.04-3.08) and the mean ratio of penile length to body length was 6.24 × 100(-1) (SD, 0.55 × 100(-1)), both of which were significantly smaller than those in Caucasian newborn infants. Buried penis was identified in 20 of 547 infants (3.7%; 95% CI, 2.1-5.2%). The first measurements of penile length at 1-12 hours were significantly smaller than the next measurements at 1-7 days (95% CI of the difference, 0.22-0.34). The 95% CI for the limits of agreement in the penile lengths measured by the two observers was -0.58 to -0.40 for the lower limit and 0.33 to 0.51 for the upper limit. These findings indicate that the penile length should be assessed after 24 hours of age by the reference standard of the same ethnicity for identifying micropenis and that buried penis is not uncommon in Japanese full-term newborns.

  15. 5 CFR 1900.100 - Cross-references to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Cross-references to employee ethical... ethical conduct standards and financial disclosure regulations. Officers and employees of the Appalachian Regional Commission Federal Staff are subject to the Standards of Ethical Conduct for Employees of the...

  16. 12 CFR 601.100 - Cross-references to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Cross-references to employee ethical conduct... employee ethical conduct standards and financial disclosure regulations. Board members, officers, and other employees of the Farm Credit Administration are subject to the Standards of Ethical Conduct for Employees of...

  17. 5 CFR 1633.1 - Cross-reference to employee ethical conduct standards and financial disclosure regulations.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Cross-reference to employee ethical... ethical conduct standards and financial disclosure regulations. Employees of the Federal Retirement Thrift Investment Board (Board) are subject to the executive branch-wide Standards of Ethical conduct at 5 CFR part...

  18. 29 CFR 0.735-1 - Cross-references to employee ethical conduct standards, financial disclosure regulations and...

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 1 2010-07-01 2010-07-01 true Cross-references to employee ethical conduct standards, financial disclosure regulations and other ethics regulations. 0.735-1 Section 0.735-1 Labor Office of the Secretary of Labor ETHICS AND CONDUCT OF DEPARTMENT OF LABOR EMPLOYEES Standards of Conduct for Current...

  19. Reference material for trace analysis by radioanalytical methods: Bowen's Kale

    International Nuclear Information System (INIS)

    Wainerdi, R.E.

    1979-01-01

    A fairly large volume of published data on 'Bowen's Kale' has been examined critically in order to develop recommendations for the use of this preparation as a 'reference material' in the standardisation and evaluation of the reliability of analytical procedures. Values are now recommended for the contents of twelve elements present in major to trace concentrations in 'Bowen's Kale'. 'Indicated values' for another 16 elements are provided. Values for 15 more elements are listed with no recommendation. The criteria adopted in categorising elements into these groups are discussed. (author)

  20. Assessment of air quality microsensors versus reference methods: The EuNetAir joint exercise

    Science.gov (United States)

    Borrego, C.; Costa, A. M.; Ginja, J.; Amorim, M.; Coutinho, M.; Karatzas, K.; Sioumis, Th.; Katsifarakis, N.; Konstantinidis, K.; De Vito, S.; Esposito, E.; Smith, P.; André, N.; Gérard, P.; Francis, L. A.; Castell, N.; Schneider, P.; Viana, M.; Minguillón, M. C.; Reimringer, W.; Otjes, R. P.; von Sicard, O.; Pohle, R.; Elen, B.; Suriano, D.; Pfister, V.; Prato, M.; Dipinto, S.; Penza, M.

    2016-12-01

    The 1st EuNetAir Air Quality Joint Intercomparison Exercise organized in Aveiro (Portugal) from 13th-27th October 2014, focused on the evaluation and assessment of environmental gas, particulate matter (PM) and meteorological microsensors, versus standard air quality reference methods through an experimental urban air quality monitoring campaign. The IDAD-Institute of Environment and Development Air Quality Mobile Laboratory was placed at an urban traffic location in the city centre of Aveiro to conduct continuous measurements with standard equipment and reference analysers for CO, NOx, O3, SO2, PM10, PM2.5, temperature, humidity, wind speed and direction, solar radiation and precipitation. The comparison of the sensor data generated by different microsensor-systems installed side-by-side with reference analysers, contributes to the assessment of the performance and the accuracy of microsensor-systems in a real-world context, and supports their calibration and further development. The overall performance of the sensors in terms of their statistical metrics and measurement profile indicates significant differences in the results depending on the platform and on the sensors considered. In terms of pollutants, some promising results were observed for O3 (r2: 0.12-0.77), CO (r2: 0.53-0.87), and NO2 (r2: 0.02-0.89). For PM (r2: 0.07-0.36) and SO2 (r2: 0.09-0.20) the results show a poor performance with low correlation coefficients between the reference and microsensor measurements. These field observations under specific environmental conditions suggest that the relevant microsensor platforms, if supported by the proper post processing and data modelling tools, have enormous potential for new strategies in air quality control.

  1. Practical utilization of recombinant AAV vector reference standards: focus on vector genomes titration by free ITR qPCR

    Directory of Open Access Journals (Sweden)

    Susan D'Costa

    2016-01-01

    Full Text Available Clinical trials using recombinant adeno-associated virus (rAAV vectors have demonstrated efficacy and a good safety profile. Although the field is advancing quickly, vector analytics and harmonization of dosage units are still a limitation for commercialization. AAV reference standard materials (RSMs can help ensure product safety by controlling the consistency of assays used to characterize rAAV stocks. The most widely utilized unit of vector dosing is based on the encapsidated vector genome. Quantitative polymerase chain reaction (qPCR is now the most common method to titer vector genomes (vg; however, significant inter- and intralaboratory variations have been documented using this technique. Here, RSMs and rAAV stocks were titered on the basis of an inverted terminal repeats (ITRs sequence-specific qPCR and we found an artificial increase in vg titers using a widely utilized approach. The PCR error was introduced by using single-cut linearized plasmid as the standard curve. This bias was eliminated using plasmid standards linearized just outside the ITR region on each end to facilitate the melting of the palindromic ITR sequences during PCR. This new “Free-ITR” qPCR delivers vg titers that are consistent with titers obtained with transgene-specific qPCR and could be used to normalize in-house product-specific AAV vector standards and controls to the rAAV RSMs. The free-ITR method, including well-characterized controls, will help to calibrate doses to compare preclinical and clinical data in the field.

  2. Practical utilization of recombinant AAV vector reference standards: focus on vector genomes titration by free ITR qPCR.

    Science.gov (United States)

    D'Costa, Susan; Blouin, Veronique; Broucque, Frederic; Penaud-Budloo, Magalie; François, Achille; Perez, Irene C; Le Bec, Christine; Moullier, Philippe; Snyder, Richard O; Ayuso, Eduard

    2016-01-01

    Clinical trials using recombinant adeno-associated virus (rAAV) vectors have demonstrated efficacy and a good safety profile. Although the field is advancing quickly, vector analytics and harmonization of dosage units are still a limitation for commercialization. AAV reference standard materials (RSMs) can help ensure product safety by controlling the consistency of assays used to characterize rAAV stocks. The most widely utilized unit of vector dosing is based on the encapsidated vector genome. Quantitative polymerase chain reaction (qPCR) is now the most common method to titer vector genomes (vg); however, significant inter- and intralaboratory variations have been documented using this technique. Here, RSMs and rAAV stocks were titered on the basis of an inverted terminal repeats (ITRs) sequence-specific qPCR and we found an artificial increase in vg titers using a widely utilized approach. The PCR error was introduced by using single-cut linearized plasmid as the standard curve. This bias was eliminated using plasmid standards linearized just outside the ITR region on each end to facilitate the melting of the palindromic ITR sequences during PCR. This new "Free-ITR" qPCR delivers vg titers that are consistent with titers obtained with transgene-specific qPCR and could be used to normalize in-house product-specific AAV vector standards and controls to the rAAV RSMs. The free-ITR method, including well-characterized controls, will help to calibrate doses to compare preclinical and clinical data in the field.

  3. GTX Reference Vehicle Structural Verification Methods and Weight Summary

    Science.gov (United States)

    Hunter, J. E.; McCurdy, D. R.; Dunn, P. W.

    2002-01-01

    The design of a single-stage-to-orbit air breathing propulsion system requires the simultaneous development of a reference launch vehicle in order to achieve the optimal mission performance. Accordingly, for the GTX study a 300-lb payload reference vehicle was preliminarily sized to a gross liftoff weight (GLOW) of 238,000 lb. A finite element model of the integrated vehicle/propulsion system was subjected to the trajectory environment and subsequently optimized for structural efficiency. This study involved the development of aerodynamic loads mapped to finite element models of the integrated system in order to assess vehicle margins of safety. Commercially available analysis codes were used in the process along with some internally developed spreadsheets and FORTRAN codes specific to the GTX geometry for mapping of thermal and pressure loads. A mass fraction of 0.20 for the integrated system dry weight has been the driver for a vehicle design consisting of state-of-the-art composite materials in order to meet the rigid weight requirements. This paper summarizes the methodology used for preliminary analyses and presents the current status of the weight optimization for the structural components of the integrated system.

  4. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa.

    Science.gov (United States)

    De Baetselier, Irith; Taylor, Douglas; Mandala, Justin; Nanda, Kavita; Van Campenhout, Christel; Agingu, Walter; Madurai, Lorna; Barsch, Eva-Maria; Deese, Jennifer; Van Damme, Lut; Crucitti, Tania

    2016-01-01

    Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs). Verification of CRRs is time consuming and often requires a statistical background. We report on an easy and cost-saving method to verify CRRs. Using a former method introduced by Sigma Diagnostics, three study sites in sub-Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants. Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected. To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory.

  5. Reference satellite selection method for GNSS high-precision relative positioning

    Directory of Open Access Journals (Sweden)

    Xiao Gao

    2017-03-01

    Full Text Available Selecting the optimal reference satellite is an important component of high-precision relative positioning because the reference satellite directly influences the strength of the normal equation. The reference satellite selection methods based on elevation and positional dilution of precision (PDOP value were compared. Results show that all the above methods cannot select the optimal reference satellite. We introduce condition number of the design matrix in the reference satellite selection method to improve structure of the normal equation, because condition number can indicate the ill condition of the normal equation. The experimental results show that the new method can improve positioning accuracy and reliability in precise relative positioning.

  6. Development of standard testing methods for nuclear-waste forms

    International Nuclear Information System (INIS)

    Mendel, J.E.; Nelson, R.D.

    1981-11-01

    Standard test methods for waste package component development and design, safety analyses, and licensing are being developed for the Nuclear Waste Materials Handbook. This paper describes mainly the testing methods for obtaining waste form materials data

  7. Comparison of analytical methods for the determination of histamine in reference canned fish samples

    Science.gov (United States)

    Jakšić, S.; Baloš, M. Ž.; Mihaljev, Ž.; Prodanov Radulović, J.; Nešić, K.

    2017-09-01

    Two screening methods for histamine in canned fish, an enzymatic test and a competitive direct enzyme-linked immunosorbent assay (CD-ELISA), were compared with the reversed-phase liquid chromatography (RP-HPLC) standard method. For enzymatic and CD-ELISA methods, determination was conducted according to producers’ manuals. For RP-HPLC, histamine was derivatized with dansyl-chloride, followed by RP-HPLC and diode array detection. Results of analysis of canned fish, supplied as reference samples for proficiency testing, showed good agreement when histamine was present at higher concentrations (above 100 mg kg-1). At a lower level (16.95 mg kg-1), the enzymatic test produced some higher results. Generally, analysis of four reference samples according to CD-ELISA and RP-HPLC showed good agreement for histamine determination (r=0.977 in concentration range 16.95-216 mg kg-1) The results show that the applied enzymatic test and CD-ELISA appeared to be suitable screening methods for the determination of histamine in canned fish.

  8. ['Gold standard', not 'golden standard'

    NARCIS (Netherlands)

    Claassen, J.A.H.R.

    2005-01-01

    In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same

  9. Determination of non-ortho polychlorinated biphenyls in environmental Standard Reference Materials.

    Science.gov (United States)

    Brubaker, W W; Schantz, M M; Wise, S A

    2000-07-01

    The concentrations of three non-ortho ("coplanar") polychlorinated biphenyls, 3,3',4,4'-tetrachlorobiphenyl (IUPAC PCB 77), 3,3',4,4',5-pentachlorobiphenyl (IUPAC PCB 126), and 3,3',4,4',5,5'-hexachlorobiphenyl (IUPAC PCB 169), were determined in five NIST Standard Reference Materials (SRMs) of environmental and biological interest. The measured levels were approximately between (0.2 to 1.3) ng/g in SRM 1588a (Organics in Cod Liver Oil), (0.3 to 9) ng/g in SRM 1944 (New York/New Jersey Waterway Sediment), (0.2 to 0.4) ng/g in SRM 1945 (Organics in Whale Blubber), (1 to 18) ng/g in SRM 2974 (Organics in Freeze-dried Mussel Tissue [Mytilus edulis]), and (0.1 to 0.4) ng/g in candidate SRM 1946 (Lake Superior Fish Tissue). PCB 169 was present at < 0.1 ng/g in SRMs 1944 and 2974.

  10. Methods to explain emission trends. From reference to realization

    International Nuclear Information System (INIS)

    Gijsen, A.; Oude Lohuis, J.

    2003-01-01

    Several methods are available to assess and determine the effects of policy measures. In this article methods to determine the effects of social and political developments on the emission of CO2 from the production of electricity in the Netherlands are discussed [nl

  11. A rule-based reference resolution method for Dutch discourse

    NARCIS (Netherlands)

    Harabagiu, S.; op den Akker, Hendrikus J.A.; Hospers, M.A.; Ferrandez, A.; Kroezen, Erna; Nijholt, Antinus; Lie, Danny

    2002-01-01

    This paper presents a knowledge-poor method for the solution of anaphoric and deictic expressions in Dutch texts. The method is developed for use in a text summarization system. Anaphora resolution plays an important role in the analysis of the original text as well as in the generation of the text

  12. 24 CFR Appendix A to Part 200 - Standards Incorporated by Reference in the Minimum Property Standards for Housing (HUD Handbook...

    Science.gov (United States)

    2010-04-01

    ... 19103, Telephone (215) 299-5400. ASTM C 12-91 Standard Practice for Installing Vitrified Clay Pipe Lines... C 216-91c Standard Specification for Facing Brick (Solid Masonry Units Made from Clay or Shale) ASTM.../78 77a Cast Iron Sanitary Drainage System with Hubless Pipe and Fittings—3/28/80 78 Polyethylene (PE...

  13. Standardization of Laser Methods and Techniques for Vibration Measurements and Calibrations

    International Nuclear Information System (INIS)

    Martens, Hans-Juergen von

    2010-01-01

    The realization and dissemination of the SI units of motion quantities (vibration and shock) have been based on laser interferometer methods specified in international documentary standards. New and refined laser methods and techniques developed by national metrology institutes and by leading manufacturers in the past two decades have been swiftly specified as standard methods for inclusion into in the series ISO 16063 of international documentary standards. A survey of ISO Standards for the calibration of vibration and shock transducers demonstrates the extended ranges and improved accuracy (measurement uncertainty) of laser methods and techniques for vibration and shock measurements and calibrations. The first standard for the calibration of laser vibrometers by laser interferometry or by a reference accelerometer calibrated by laser interferometry (ISO 16063-41) is on the stage of a Draft International Standard (DIS) and may be issued by the end of 2010. The standard methods with refined techniques proved to achieve wider measurement ranges and smaller measurement uncertainties than that specified in the ISO Standards. The applicability of different standardized interferometer methods to vibrations at high frequencies was recently demonstrated up to 347 kHz (acceleration amplitudes up to 350 km/s 2 ). The relative deviations between the amplitude measurement results of the different interferometer methods that were applied simultaneously, differed by less than 1% in all cases.

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

    Science.gov (United States)

    Peart, D.B.; Antweiler, Ronald C.; Taylor, Howard 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.

  15. Standard Test Method for Gel Time of Carbon Fiber-Epoxy Prepreg

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 This test method covers the determination of gel time of carbon fiber-epoxy tape and sheet. The test method is suitable for the measurement of gel time of resin systems having either high or low viscosity. 1.2 The values stated in SI units are to be regarded as standard. The values in parentheses are for reference only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  16. Baseline Assessment of 25-Hydroxyvitamin D Reference Material and Proficiency Testing/External Quality Assurance Material Commutability: A Vitamin D Standardization Program Study.

    Science.gov (United States)

    Phinney, Karen W; Sempos, Christopher T; Tai, Susan S-C; Camara, Johanna E; Wise, Stephen A; Eckfeldt, John H; Hoofnagle, Andrew N; Carter, Graham D; Jones, Julia; Myers, Gary L; Durazo-Arvizu, Ramon; Miller, W Greg; Bachmann, Lorin M; Young, Ian S; Pettit, Juanita; Caldwell, Grahame; Liu, Andrew; Brooks, Stephen P J; Sarafin, Kurtis; Thamm, Michael; Mensink, Gert B M; Busch, Markus; Rabenberg, Martina; Cashman, Kevin D; Kiely, Mairead; Galvin, Karen; Zhang, Joy Y; Kinsella, Michael; Oh, Kyungwon; Lee, Sun-Wha; Jung, Chae L; Cox, Lorna; Goldberg, Gail; Guberg, Kate; Meadows, Sarah; Prentice, Ann; Tian, Lu; Brannon, Patsy M; Lucas, Robyn M; Crump, Peter M; Cavalier, Etienne; Merkel, Joyce; Betz, Joseph M

    2017-09-01

    The Vitamin D Standardization Program (VDSP) coordinated a study in 2012 to assess the commutability of reference materials and proficiency testing/external quality assurance materials for total 25-hydroxyvitamin D [25(OH)D] in human serum, the primary indicator of vitamin D status. A set of 50 single-donor serum samples as well as 17 reference and proficiency testing/external quality assessment materials were analyzed by participating laboratories that used either immunoassay or LC-MS methods for total 25(OH)D. The commutability test materials included National Institute of Standards and Technology Standard Reference Material 972a Vitamin D Metabolites in Human Serum as well as materials from the College of American Pathologists and the Vitamin D External Quality Assessment Scheme. Study protocols and data analysis procedures were in accordance with Clinical and Laboratory Standards Institute guidelines. The majority of the test materials were found to be commutable with the methods used in this commutability study. These results provide guidance for laboratories needing to choose appropriate reference materials and select proficiency or external quality assessment programs and will serve as a foundation for additional VDSP studies.

  17. A simple preparation of calibration curve standards of 134Cs and 137Cs by serial dilution of a standard reference material

    International Nuclear Information System (INIS)

    Labrecque, J.J.; Rosales, P.A.

    1990-01-01

    Two sets of calibration standards for 134 Cs and 137 Cs were prepared by small serial dilution of a natural matrix standard reference material, IAEA-154 whey powder. The first set was intended to screen imported milk powders which were suspected to be contaminated with 134 Cs and 137 Cs. Their concentration ranged from 40 to 400 Bq/kg. The other set of calibration standards was prepared to measure the environmental levels of 137 Cs in commercial Venezuelan milk powders. Their concentration ranged from 3 to 10 Bq/kg of 137 Cs. The accuracy of these calibration curves was checked by IAEA-152 and A-14 milk powders. Their measured values were in good agreement with their certified values. Finally, it is shown that these preparation techniques using serial dilution of a standard reference material were simple, rapid, precise, accurate and cost-effective. (author) 5 refs.; 5 figs.; 3 tabs

  18. Reference value standards and primary standards for pH measurements in D2O and aqueous-organic solvent mixtures: new accessions and assessments

    International Nuclear Information System (INIS)

    Mussini, P.R.; Mussini, T.; Rondinini, S.

    1997-01-01

    Recommended Reference Value Standards based on the potassium hydro-genphthalate buffer at various temperatures are reported for pH measurements in various binary solvent mixtures of water with eight organic solvents: methanol, ethanol, 2-propanol, 1,2-ethanediol, 2-methoxyethanol (''methylcellosolve''), acetonitrile, 1,4-dioxane, and dimethyl sulfoxide, together with Reference Value Standard based on the potassium deuterium phthalate buffer for pD measurements in D 2 O. In addition are reported Primary Standards for pH based on numerous buffers in various binary solvent mixtures of water with methanol, ethanol, and dimethyl sulfoxide, together with Primary Standards for pD in D 2 O based on the citrate, phosphate and carbonate buffers. (author)

  19. Solid phase speciation of arsenic by sequential extraction in standard reference materials and industrially contaminated soil samples

    International Nuclear Information System (INIS)

    Herreweghe, Samuel van; Swennen, Rudy; Vandecasteele, Carlo; Cappuyns, Valerie

    2003-01-01

    Leaching experiments, a mineralogical survey and larger samples are preferred when arsenic is present as discrete mineral phases. - Availability, mobility, (phyto)toxicity and potential risk of contaminants is strongly affected by the manner of appearance of elements, the so-called speciation. Operational fractionation methods like sequential extractions have been applied for a long time to determine the solid phase speciation of heavy metals since direct determination of specific chemical compounds can not always be easily achieved. The three-step sequential extraction scheme recommended by the BCR and two extraction schemes based on the phosphorus-like protocol proposed by Manful (1992, Occurrence and Ecochemical Behaviours of Arsenic in a Goldsmelter Impacted Area in Ghana, PhD dissertation, at the RUG) were applied to four standard reference materials (SRM) and to a batch of samples from industrially contaminated sites, heavily contaminated with arsenic and heavy metals. The SRM 2710 (Montana soil) was found to be the most useful reference material for metal (Mn, Cu, Zn, As, Cd and Pb) fractionation using the BCR sequential extraction procedure. Two sequential extraction schemes were developed and compared for arsenic with the aim to establish a better fractionation and recovery rate than the BCR-scheme for this element in the SRM samples. The major part of arsenic was released from the heavily contaminated samples after NaOH-extraction. Inferior extraction variability and recovery in the heavily contaminated samples compared to SRMs could be mainly contributed to subsample heterogeneity

  20. Quality assessment of Chrysanthemum indicum Flower by simultaneous quantification of six major ingredients using a single reference standard combined with HPLC fingerprint analysis

    Directory of Open Access Journals (Sweden)

    Jiao He

    2016-04-01

    Full Text Available Chrysanthemum indicum Flower is usually consumed as functional food. This paper described an improved total quality assessment method for Chrysanthemum indicum Flower by simultaneous quantitation using a single standard to determine multi-components method combined with high performance liquid chromatography fingerprint analysis. Six main components of Chrysanthemum indicum Flower including two flavonoids and four phenolic acids were simultaneously quantified using linarin as the internal reference standard. The method was fully validated with respect to linearity, precision, accuracy, robustness and stability. The validated method was successfully applied to the analysis of thirty three batches of Chrysanthemum indicum Flower samples. Under the same chromatographic conditions, fingerprint analysis in combination with Similarity analysis and principal component analysis was performed to identify the samples from different regions. In general, an effective assessment using a single standard to determinate multi-components method combined with fingerprint analysis make the reliable qualitation and quantitation analysis of Chrysanthemum indicum Flower available.

  1. A global multicenter study on reference values: 1. Assessment of methods for derivation and comparison of reference intervals.

    Science.gov (United States)

    Ichihara, Kiyoshi; Ozarda, Yesim; Barth, Julian H; Klee, George; Qiu, Ling; Erasmus, Rajiv; Borai, Anwar; Evgina, Svetlana; Ashavaid, Tester; Khan, Dilshad; Schreier, Laura; Rolle, Reynan; Shimizu, Yoshihisa; Kimura, Shogo; Kawano, Reo; Armbruster, David; Mori, Kazuo; Yadav, Binod K

    2017-04-01

    The IFCC Committee on Reference Intervals and Decision Limits coordinated a global multicenter study on reference values (RVs) to explore rational and harmonizable procedures for derivation of reference intervals (RIs) and investigate the feasibility of sharing RIs through evaluation of sources of variation of RVs on a global scale. For the common protocol, rather lenient criteria for reference individuals were adopted to facilitate harmonized recruitment with planned use of the latent abnormal values exclusion (LAVE) method. As of July 2015, 12 countries had completed their study with total recruitment of 13,386 healthy adults. 25 analytes were measured chemically and 25 immunologically. A serum panel with assigned values was measured by all laboratories. RIs were derived by parametric and nonparametric methods. The effect of LAVE methods is prominent in analytes which reflect nutritional status, inflammation and muscular exertion, indicating that inappropriate results are frequent in any country. The validity of the parametric method was confirmed by the presence of analyte-specific distribution patterns and successful Gaussian transformation using the modified Box-Cox formula in all countries. After successful alignment of RVs based on the panel test results, nearly half the analytes showed variable degrees of between-country differences. This finding, however, requires confirmation after adjusting for BMI and other sources of variation. The results are reported in the second part of this paper. The collaborative study enabled us to evaluate rational methods for deriving RIs and comparing the RVs based on real-world datasets obtained in a harmonized manner. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  2. 40 CFR 75.22 - Reference test methods.

    Science.gov (United States)

    2010-07-01

    ... tester may also opt to use the sample recovery and preparation procedures in ASTM D6784-02 (incorporated... 75.22 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED... site and sample traverses. (2) Method 2 or its allowable alternatives, as provided in appendix A to...

  3. Standard methods for sampling freshwater fishes: Opportunities for international collaboration

    Science.gov (United States)

    Bonar, Scott A.; Mercado-Silva, Norman; Hubert, Wayne A.; Beard, Douglas; Dave, Göran; Kubečka, Jan; Graeb, Brian D. S.; Lester, Nigel P.; Porath, Mark T.; Winfield, Ian J.

    2017-01-01

    With publication of Standard Methods for Sampling North American Freshwater Fishes in 2009, the American Fisheries Society (AFS) recommended standard procedures for North America. To explore interest in standardizing at intercontinental scales, a symposium attended by international specialists in freshwater fish sampling was convened at the 145th Annual AFS Meeting in Portland, Oregon, in August 2015. Participants represented all continents except Australia and Antarctica and were employed by state and federal agencies, universities, nongovernmental organizations, and consulting businesses. Currently, standardization is practiced mostly in North America and Europe. Participants described how standardization has been important for management of long-term data sets, promoting fundamental scientific understanding, and assessing efficacy of large spatial scale management strategies. Academics indicated that standardization has been useful in fisheries education because time previously used to teach how sampling methods are developed is now more devoted to diagnosis and treatment of problem fish communities. Researchers reported that standardization allowed increased sample size for method validation and calibration. Group consensus was to retain continental standards where they currently exist but to further explore international and intercontinental standardization, specifically identifying where synergies and bridges exist, and identify means to collaborate with scientists where standardization is limited but interest and need occur.

  4. Retrospective Analysis of NIST Standard Reference Material 1450, Fibrous Glass Board, for Thermal Insulation Measurements

    Science.gov (United States)

    Zarr, Robert R; Heckert, N Alan; Leigh, Stefan D

    2014-01-01

    Thermal conductivity data acquired previously for the establishment of Standard Reference Material (SRM) 1450, Fibrous Glass Board, as well as subsequent renewals 1450a, 1450b, 1450c, and 1450d, are re-analyzed collectively and as individual data sets. Additional data sets for proto-1450 material lots are also included in the analysis. The data cover 36 years of activity by the National Institute of Standards and Technology (NIST) in developing and providing thermal insulation SRMs, specifically high-density molded fibrous-glass board, to the public. Collectively, the data sets cover two nominal thicknesses of 13 mm and 25 mm, bulk densities from 60 kg·m−3 to 180 kg·m−3, and mean temperatures from 100 K to 340 K. The analysis repetitively fits six models to the individual data sets. The most general form of the nested set of multilinear models used is given in the following equation: λ(ρ,T)=a0+a1ρ+a2T+a3T3+a4e−(T−a5a6)2where λ(ρ,T) is the predicted thermal conductivity (W·m−1·K−1), ρ is the bulk density (kg·m−3), T is the mean temperature (K) and ai (for i = 1, 2, … 6) are the regression coefficients. The least squares fit results for each model across all data sets are analyzed using both graphical and analytic techniques. The prevailing generic model for the majority of data sets is the bilinear model in ρ and T. λ(ρ,T)=a0+a1ρ+a2T One data set supports the inclusion of a cubic temperature term and two data sets with low-temperature data support the inclusion of an exponential term in T to improve the model predictions. Physical interpretations of the model function terms are described. Recommendations for future renewals of SRM 1450 are provided. An Addendum provides historical background on the origin of this SRM and the influence of the SRM on external measurement programs. PMID:26601034

  5. Determination of polychlorinated dibenzo-p-dioxin and dibenzofuran congeners in air particulate and marine sediment standard reference materials (SRMs).

    Science.gov (United States)

    Chiu, C H; Turle, R; Poole, G; Thibert, B; Brubaker, W W; Schantz, M M; Wise, S A

    2001-02-01

    Due to the limited number of environmental matrix certified reference materials (CRMs) with assigned values for natural levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), an interlaboratory study was undertaken by the National Institute of Standards and Technology (NIST) and Environment Canada to establish reference concentration values for selected PCDD/Fs in two well-characterized NIST Standard Reference Materials (SRMs): SRM 1649a (Urban Dust) and SRM 1944 (New York/New Jersey Waterway Sediment). Results from 14 laboratories were used to provide reference values for the seventeen 2, 3, 7, 8-substituted PCDD/F congeners, the totals for individual tetra- through hepta-substituted PCDD/F homologues, and the total amount of tetra- through hepta-substituted PCDD/Fs. The mass fractions for the individual 2, 3, 7, 8-substituted congeners range from approximately 0.01 microg/kg to 7 microg/kg dry mass.

  6. Global panel of HIV-1 Env reference strains for standardized assessments of vaccine-elicited neutralizing antibodies.

    Science.gov (United States)

    deCamp, Allan; Hraber, Peter; Bailer, Robert T; Seaman, Michael S; Ochsenbauer, Christina; Kappes, John; Gottardo, Raphael; Edlefsen, Paul; Self, Steve; Tang, Haili; Greene, Kelli; Gao, Hongmei; Daniell, Xiaoju; Sarzotti-Kelsoe, Marcella; Gorny, Miroslaw K; Zolla-Pazner, Susan; LaBranche, Celia C; Mascola, John R; Korber, Bette T; Montefiori, David C

    2014-03-01

    Standardized assessments of HIV-1 vaccine-elicited neutralizing antibody responses are complicated by the genetic and antigenic variability of the viral envelope glycoproteins (Envs). To address these issues, suitable reference strains are needed that are representative of the global epidemic. Several panels have been recommended previously, but no clear answers have been available on how many and which strains are best suited for this purpose. We used a statistical model selection method to identify a global panel of reference Env clones from among 219 Env-pseudotyped viruses assayed in TZM-bl cells with sera from 205 HIV-1-infected individuals. The Envs and sera were sampled globally from diverse geographic locations and represented all major genetic subtypes and circulating recombinant forms of the virus. Assays with a panel size of only nine viruses adequately represented the spectrum of HIV-1 serum neutralizing activity seen with the larger panel of 219 viruses. An optimal panel of nine viruses was selected and augmented with three additional viruses for greater genetic and antigenic coverage. The spectrum of HIV-1 serum neutralizing activity seen with the final 12-virus panel closely approximated the activity seen with subtype-matched viruses. Moreover, the final panel was highly sensitive for detection of many of the known broadly neutralizing antibodies. For broader assay applications, all 12 Env clones were converted to infectious molecular clones using a proviral backbone carrying a Renilla luciferase reporter gene (Env.IMC.LucR viruses). This global panel should facilitate highly standardized assessments of vaccine-elicited neutralizing antibodies across multiple HIV-1 vaccine platforms in different parts of the world. An effective HIV-1 vaccine will need to overcome the extraordinary genetic variability of the virus, where most variation occurs in the viral envelope glycoproteins that are the sole targets for neutralizing antibodies. Efforts to elicit

  7. An open source, 3D printed preclinical MRI phantom for repeated measures of contrast agents and reference standards.

    Science.gov (United States)

    Cox, B L; Ludwig, K D; Adamson, E B; Eliceiri, K W; Fain, S B

    2018-03-01

    In medical imaging, clinicians, researchers and technicians have begun to use 3D printing to create specialized phantoms to replace commercial ones due to their customizable and iterative nature. Presented here is the design of a 3D printed open source, reusable magnetic resonance imaging (MRI) phantom, capable of flood-filling, with removable samples for measurements of contrast agent solutions and reference standards, and for use in evaluating acquisition techniques and image reconstruction performance. The phantom was designed using SolidWorks, a computer-aided design software package. The phantom consists of custom and off-the-shelf parts and incorporates an air hole and Luer Lock system to aid in flood filling, a marker for orientation of samples in the filled mode and bolt and tube holes for assembly. The cost of construction for all materials is under $90. All design files are open-source and available for download. To demonstrate utility, B 0 field mapping was performed using a series of gadolinium concentrations in both the unfilled and flood-filled mode. An excellent linear agreement (R 2 >0.998) was observed between measured relaxation rates (R 1 /R 2 ) and gadolinium concentration. The phantom provides a reliable setup to test data acquisition and reconstruction methods and verify physical alignment in alternative nuclei MRI techniques (e.g. carbon-13 and fluorine-19 MRI). A cost-effective, open-source MRI phantom design for repeated quantitative measurement of contrast agents and reference standards in preclinical research is presented. Specifically, the work is an example of how the emerging technology of 3D printing improves flexibility and access for custom phantom design.

  8. MRI of the normal appendix in children: data toward a new reference standard

    Energy Technology Data Exchange (ETDEWEB)

    Swenson, David W. [Alpert Medical School of Brown University and Rhode Island Hospital, Department of Diagnostic Imaging, Providence, RI (United States); Schooler, Gary R. [Duke University Medical Center, Department of Radiology, Durham, NC (United States); Stamoulis, Catherine; Lee, Edward Y. [Boston Children' s Hospital and Harvard Medical School, Department of Radiology, Boston, MA (United States)

    2016-06-15

    Magnetic resonance imaging (MRI) might prove useful in the diagnostic evaluation of pediatric appendicitis in the effort to avoid exposing children to the ionizing radiation of CT, yet there is a paucity of literature describing the normal range of appearances of the pediatric appendix on MRI. To investigate MRI characteristics of the normal appendix to aid in establishing a reference standard in the pediatric population. We conducted a retrospective study of children and young adults (≤18 years of age) who underwent lumbar spine or pelvis MRI between Jan. 1, 2013, and Dec. 31, 2013, for indications unrelated to appendicitis. Two board-certified radiologists independently reviewed all patients' MRI examinations for appendix visualization, diameter, intraluminal content signal, and presence of periappendiceal inflammation or free fluid. We used the Cohen kappa statistic and Spearman correlation coefficient to assess reader agreement on qualitative and quantitative data, respectively. Three hundred forty-six patients met inclusion criteria. Both readers visualized the appendix in 192/346 (55.5%) patients (kappa = 0.88, P < 0.0001). Estimated median appendix diameter was 5 mm for reader 1 and 6 mm for reader 2 ([25th, 75th] quartiles = [5, 6] mm; range, 2-11 mm; r = 0.81, P < 0.0001). Appendix intraluminal signal characteristics were variable. Periappendiceal inflammation was present in 0/192 (0%) and free fluid in 6/192 (3.1%) MRI examinations (kappa = 1.0). The normal appendix was seen on MRI in approximately half of pediatric patients, with a mean diameter of ∝5-6 mm, variable intraluminal signal characteristics, no adjacent inflammatory changes, and rare surrounding free fluid. (orig.)

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

    Science.gov (United States)

    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.

  10. Standard and reference materials for environmental science. Part 1. Technical memo

    Energy Technology Data Exchange (ETDEWEB)

    Cantillo, A.Y.

    1995-11-01

    This is the fourth edition of the catalog of reference materials suited for use in environmental science, originally compiled in 1986 for NOAA, IOC, and UNEP. The catalog lists more than 1200 reference materials from 28 producers and contains information about their proper use, sources, availability, and analyte concentrations. Indices are included for elements, isotopes, and organic compounds, as are cross references to CAS registry numbers, alternate names, and chemical structures of selected organic compounds.

  11. Standard and reference materials for environmental science. Part 2. Technical memo

    Energy Technology Data Exchange (ETDEWEB)

    Cantillo, A.Y.

    1995-11-01

    This is the fourth edition of the catalog of reference materials suited for use in environmental science, originally compiled in 1986 for NOAA, IOC, and UNEP. The catalog lists more than 1200 reference materials from 28 producers and contains information about their proper use, sources, availability, and analyte concentrations. Indices are included for elements, isotopes, and organic compounds, as are cross references to CAS registry numbers, alternate names, and chemical structures of selected organic compounds.

  12. ICP-MS determination of boron: method optimization during preparation of graphite reference material for boron

    International Nuclear Information System (INIS)

    Granthali, S.K.; Shailaja, P.P.; Mainsha, V.; Venkatesh, K.; Kallola, K.S.; Sanjukta, A.K.

    2017-01-01

    Graphite finds widespread use in nuclear reactors as moderator, reflector, and fuel fabricating components because of its thermal stability and integrity. The manufacturing process consists of various mixing, moulding and baking operations followed by heat-treatment between 2500 °C and 3000 °C. The high temperature treatment is required to drive the amorphous carbon-to-graphite phase transformation. Since synthetic graphite is processed at high temperature, impurity concentrations in the precursor carbon get significantly reduced due to volatilization. However boron may might partly gets converted into boron carbide at high temperatures in the carbon environment of graphite and remains stable (B_4C: boiling point 3500 °C) in the matrix. Literature survey reveals the use of various methods for determination of boron. Previously we have developed a method for determination of boron in graphite electrodes using inductively coupled plasma mass spectrometry (ICP-MS). The method involves removal of graphite matrix by ignition of the sample at 800°C in presence of saturated barium hydroxide solution to prevent the loss of boron. Here we are reporting a modification in the method by using calcium carbonate in place of barium hydroxide and using beryllium (Be) as an internal standard, which resulted in a better precession. The method was validated by spike recovery experiments as well as using another technique viz. Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The modified method was applied in evaluation of boron concentration in the graphite reference material prepared

  13. Standard test methods for rockwell hardness of metallic materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials by the Rockwell indentation hardness principle. This standard provides the requirements for Rockwell hardness machines and the procedures for performing Rockwell hardness tests. 1.2 This standard includes additional requirements in annexes: Verification of Rockwell Hardness Testing Machines Annex A1 Rockwell Hardness Standardizing Machines Annex A2 Standardization of Rockwell Indenters Annex A3 Standardization of Rockwell Hardness Test Blocks Annex A4 Guidelines for Determining the Minimum Thickness of a Test Piece Annex A5 Hardness Value Corrections When Testing on Convex Cylindrical Surfaces Annex A6 1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test. List of ASTM Standards Giving Hardness Values Corresponding to Tensile Strength Appendix X1 Examples of Procedures for Determining Rockwell Hardness Uncertainty Appendix X...

  14. Standard test methods for rockwell hardness of metallic materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallic materials by the Rockwell indentation hardness principle. This standard provides the requirements for Rockwell hardness machines and the procedures for performing Rockwell hardness tests. 1.2 This standard includes additional requirements in annexes: Verification of Rockwell Hardness Testing Machines Annex A1 Rockwell Hardness Standardizing Machines Annex A2 Standardization of Rockwell Indenters Annex A3 Standardization of Rockwell Hardness Test Blocks Annex A4 Guidelines for Determining the Minimum Thickness of a Test Piece Annex A5 Hardness Value Corrections When Testing on Convex Cylindrical Surfaces Annex A6 1.3 This standard includes nonmandatory information in appendixes which relates to the Rockwell hardness test. List of ASTM Standards Giving Hardness Values Corresponding to Tensile Strength Appendix X1 Examples of Procedures for Determining Rockwell Hardness Uncertainty Appendix X...

  15. Standard methods for sampling freshwater fishes: opportunities for international collaboration

    OpenAIRE

    Bonar, Scott A.; Mercado-Silva, Norman; Hubert, Wayne A.; Beard, T. Douglas; Dave, Göran; Kubečka, Jan; Graeb, Brian D.S.; Lester, Nigel P.; Porath, Mark; Winfield, Ian J.

    2017-01-01

    With publication of Standard Methods for Sampling North American Freshwater Fishes in 2009, the American Fisheries Society (AFS) recommended standard procedures for North America. To explore interest in standardizing at intercontinental scales, a symposium attended by international specialists in freshwater fish sampling was convened at the 145th Annual AFS Meeting in Portland, Oregon, in August 2015. Participants represented all continents except Australia and Antarctica and were employed by...

  16. A Reference Implementation of the OGC CSW EO Standard for the ESA HMA-T project

    Science.gov (United States)

    Bigagli, Lorenzo; Boldrini, Enrico; Papeschi, Fabrizio; Vitale, Fabrizio

    2010-05-01

    This work was developed in the context of the ESA Heterogeneous Missions Accessibility (HMA) project, whose main objective is to involve the stakeholders, namely National space agencies, satellite or mission owners and operators, in an harmonization and standardization process of their ground segment services and related interfaces. Among HMA objectives was the specification, conformance testing, and experimentation of two Extension Packages (EPs) of the ebRIM Application Profile (AP) of the OGC Catalog Service for the Web (CSW) specification: the Earth Observation Products (EO) EP (OGC 06-131) and the Cataloguing of ISO Metadata (CIM) EP (OGC 07-038). Our contributions have included the development and deployment of Reference Implementations (RIs) for both the above specifications, and their integration with the ESA Service Support Environment (SSE). The RIs are based on the GI-cat framework, an implementation of a distributed catalog service, able to query disparate Earth and Space Science data sources (e.g. OGC Web Services, Unidata THREDDS) and to expose several standard interfaces for data discovery (e.g. OGC CSW ISO AP). Following our initial planning, the GI-cat framework has been extended in order to expose the CSW.ebRIM-CIM and CSW.ebRIM-EO interfaces, and to distribute queries to CSW.ebRIM-CIM and CSW.ebRIM-EO data sources. We expected that a mapping strategy would suffice for accommodating CIM, but this proved to be unpractical during implementation. Hence, a model extension strategy was eventually implemented for both the CIM and EO EPs, and the GI-cat federal model was enhanced in order to support the underlying ebRIM AP. This work has provided us with new insights into the different data models for geospatial data, and the technologies for their implementation. The extension is used by suitable CIM and EO profilers (front-end mediator components) and accessors (back-end mediator components), that relate ISO 19115 concepts to EO and CIM ones. Moreover

  17. Multivariate methods for analysis of environmental reference materials using laser-induced breakdown spectroscopy

    Directory of Open Access Journals (Sweden)

    Shikha Awasthi

    2017-06-01

    Full Text Available Analysis of emission from laser-induced plasma has a unique capability for quantifying the major and minor elements present in any type of samples under optimal analysis conditions. Chemometric techniques are very effective and reliable tools for quantification of multiple components in complex matrices. The feasibility of laser-induced breakdown spectroscopy (LIBS in combination with multivariate analysis was investigated for the analysis of environmental reference materials (RMs. In the present work, different (Certified/Standard Reference Materials of soil and plant origin were analyzed using LIBS and the presence of Al, Ca, Mg, Fe, K, Mn and Si were identified in the LIBS spectra of these materials. Multivariate statistical methods (Partial Least Square Regression and Partial Least Square Discriminant Analysis were employed for quantitative analysis of the constituent elements using the LIBS spectral data. Calibration models were used to predict the concentrations of the different elements of test samples and subsequently, the concentrations were compared with certified concentrations to check the authenticity of models. The non-destructive analytical method namely Instrumental Neutron Activation Analysis (INAA using high flux reactor neutrons and high resolution gamma-ray spectrometry was also used for intercomparison of results of two RMs by LIBS.

  18. Long-term response to genomic selection: effects of estimation method and reference population structure for different genetic architectures.

    Science.gov (United States)

    Bastiaansen, John W M; Coster, Albart; Calus, Mario P L; van Arendonk, Johan A M; Bovenhuis, Henk

    2012-01-24

    Genomic selection has become an important tool in the genetic improvement of animals and plants. The objective of this study was to investigate the impacts of breeding value estimation method, reference population structure, and trait genetic architecture, on long-term response to genomic selection without updating marker effects. Three methods were used to estimate genomic breeding values: a BLUP method with relationships estimated from genome-wide markers (GBLUP), a Bayesian method, and a partial least squares regression method (PLSR). A shallow (individuals from one generation) or deep reference population (individuals from five generations) was used with each method. The effects of the different selection approaches were compared under four different genetic architectures for the trait under selection. Selection was based on one of the three genomic breeding values, on pedigree BLUP breeding values, or performed at random. Selection continued for ten generations. Differences in long-term selection response were small. For a genetic architecture with a very small number of three to four quantitative trait loci (QTL), the Bayesian method achieved a response that was 0.05 to 0.1 genetic standard deviation higher than other methods in generation 10. For genetic architectures with approximately 30 to 300 QTL, PLSR (shallow reference) or GBLUP (deep reference) had an average advantage of 0.2 genetic standard deviation over the Bayesian method in generation 10. GBLUP resulted in 0.6% and 0.9% less inbreeding than PLSR and BM and on average a one third smaller reduction of genetic variance. Responses in early generations were greater with the shallow reference population while long-term response was not affected by reference population structure. The ranking of estimation methods was different with than without selection. Under selection, applying GBLUP led to lower inbreeding and a smaller reduction of genetic variance while a similar response to selection was

  19. Standard test method for galling resistance of material couples

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers a laboratory test that ranks the galling resistance of material couples using a quantitative measure. Bare metals, alloys, nonmetallic materials, coatings, and surface modified materials may be evaluated by this test method. 1.2 This test method is not designed for evaluating the galling resistance of material couples sliding under lubricated conditions, because galling usually will not occur under lubricated sliding conditions using this test method. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  20. Analytical chemistry methods for boron carbide absorber material. [Standard

    Energy Technology Data Exchange (ETDEWEB)

    DELVIN WL

    1977-07-01

    This standard provides analytical chemistry methods for the analysis of boron carbide powder and pellets for the following: total C and B, B isotopic composition, soluble C and B, fluoride, chloride, metallic impurities, gas content, water, nitrogen, and oxygen. (DLC)

  1. Preparation and evaluation of reference materials for accountancy analysis. (1) Preparation and evaluation method

    International Nuclear Information System (INIS)

    Takamatsu, Mai; Kacchi, Tomokazu; Murakami, Toshiki; Ai, Hironobu; Sumi, Mika; Abe, Katsuo; Kageyama, Tomio; Nakazawa, Hiroaki

    2009-01-01

    Isotope dilution mass spectrometry method used for the accountancy analysis at nuclear fuel facilities requires the standard materials called LSD (Large Size Dried) spike. Generally, LSD spikes are prepared from certified reference materials (CRMs) which supplied from foreign laboratories. However, the difficulty of Pu CRM importation is increasing. It is important for safeguards to attain and continue high reliable accountancy analysis and stable securing of LSD spike is essential. Therefore, in order to conserve CRMs, several types of LSD spike were prepared under collaboration work between JAEA and JNFL, such as the amount of nuclear material in one LSD spike is decreased and others. Practical test with actual samples were performed at JNFL Rokkasho reprocessing plant, and those results were compared with the results obtained by using LSD spike which supplied from foreign laboratory. Preparation and verification analysis of LSD spikes and evaluation of uncertainty based on ISO-GUM will be presented. (author)

  2. Quine's Double Standard: Undermining the Indispensability Argument via the Indeterminacy of Reference

    Directory of Open Access Journals (Sweden)

    Otávio Bueno

    2003-12-01

    Full Text Available Quine has famously put forward the indispensability argument to force belief in the existence of mathematical objects (such as classes due to their indispensability to our best theories of the world (Quine 1960. Quine has also advocated the indeterminacy of reference argument, according to which reference is dramatically indeterminate: given a language, there’s no unique reference relation for that language (see Quine 1969a. In this paper, I argue that these two arguments are in conflict with each other. Whereas the indispensability argument supports realism about mathematics, the indeterminacy of reference argument, when applied to mathematics, provides a powerful strategy in support of mathematical anti-realism. I conclude the paper by indicating why the indeterminacy of reference phenomenon should be preferred over the considerations regarding indispensability. In the end, even the Quinean shouldn’t be a realist (platonist about mathematics.

  3. Standard test methods for characterizing duplex grain sizes

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2002-01-01

    1.1 These test methods provide simple guidelines for deciding whether a duplex grain size exists. The test methods separate duplex grain sizes into one of two distinct classes, then into specific types within those classes, and provide systems for grain size characterization of each type. 1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to consult appropriate safety and health practices and determine the applicability of regulatory limitations prior to its use.

  4. Standard and reference materials for marine science. Third edition. Technical memo

    International Nuclear Information System (INIS)

    Cantillo, A.Y.

    1992-08-01

    The third edition of the catalog of reference materials suited for use in marine science, originally compiled in 1986 for NOAA, IOC, and UNEP. The catalog lists close to 2,000 reference materials from sixteen producers and contains information about their proper use, sources, availability, and analyte concentrations. Indices are included for elements, isotopes, and organic compounds, as are cross references to CAS registry numbers, alternate names, and chemical structures of selected organic compounds. The catalog is being published independently by both NOAA and IOC/UNEP and is available from NOAA/NOS/ORCA in electronic form

  5. Element concentrations in candidate biological and environmental reference materials by k0-standardized INAA

    International Nuclear Information System (INIS)

    Freitas, M.C.

    1993-01-01

    K 0 -Based Neutron Activation Analysis (k 0 INAA) was used to analyze the candidate reference materials Apple Leaves and Peach Leaves, and Oriental Tobacco Leaves and Virginia Tobacco Leaves. Concentration values for 27 elements were measured. The accuracy was ascertained by analysis of two certified reference materials. NIST 1572 Citrus Leaves and 1573 Tomato Leaves. The homogeneity test of the IAEA Evernia prunastri candidate reference material in aliquots ≥ 100 mg is extended to the elements Sc, Cr, Fe, Co, Zn, Rb, Sb, Cs, Ba, Ce and Th. (orig.)

  6. Standard Test Method for Resin Flow of Carbon Fiber-Epoxy Prepreg

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 This test method covers the determination of the amount of resin flow that will take place from prepreg tape or sheet under given conditions of temperature and pressure. 1.2 The values stated in SI units are to be regarded as standard. The values in parentheses are for reference only. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  7. Influence of adsorption and deproteination on potential free thyroxine reference methods

    DEFF Research Database (Denmark)

    Holm, Steen S; Andreasen, Lisbeth; Hansen, Palle Steen

    2002-01-01

    There is a need for consensus concerning reference methods to be used for calibration of commercial free-thyroxine (FT(4)) assays.......There is a need for consensus concerning reference methods to be used for calibration of commercial free-thyroxine (FT(4)) assays....

  8. Characterization of human lymphoid cell lines GM9947 and GM9948 as intra- and interlaboratory reference standards for DNA typing

    Energy Technology Data Exchange (ETDEWEB)

    Fregeau, C.J.; Elliott, J.C.; Fourney, R.M. [RCMP Central Forensic Laboratory, Ottawa, Ontario (Canada)] [and others

    1995-07-20

    The incorporation of reference DNA is crucial to the validation of any DNA typing protocol. Currently, reference DNA standards are restricted to molecular size DNA ladders and/or tumor cell line DNA. Either of these, however, presents some limitations. We have rigorously characterized two Epstein-Barr virus (EBV)-immortalized human lymphoid cell lines-GM9947 (female) and GM9948 (male)-to determine their suitability as alternative in-line standards for three widely employed allele profiling strategies. Twenty-one highly polymorphic VNTR-based allelic systems (7 RFLPs, 2 AmpFLPs, and 12 STRs) distributed over 12 chromosomes were scrutinized along with 3 gender-based discriminatory systems. The genetic stability of each locus was confirmed over a period of 225 in vitro population doublings. Allele size estimates and degree of informativeness for each of the 21 VNTR systems were compiled. The reproducibility of allele scoring by traditional RFLP analyses, using both cell lines as reference standards, was also verified by an interlaboratory validation study involving 13 analysts from two geographically distinct forensic laboratories. Taken together, our data indicate that GM9947 and GM9948 genomic DNAs could be adopted as reliable reference standards for DNA typing. 82 refs., 3 figs., 8 tabs.

  9. Occupational hazard: radiation exposure for the urologist: developing a reference standard

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Seth A.; Rangarajan, Sriram S.; Chen, Tony; Palazzi, Kerrin L.; Langford, J. Scott; Sur, Roger L., E-mail: rlsur@ucsd.edu [Department of Surgery and Division of Urology, U C San Diego Health Science System, San Diego, CA (United States)

    2013-03-15

    Introduction: to date, there is a paucity of literature offering practicing urologists a reference for the amount of radiation exposure received while surgically managing urolithiasis. This study examines the cumulative radiation exposure of an urologist over 9 months. Materials and methods: We present a case series of fluoroscopic exposures of an experienced stone surgeon operating at an academic comprehensive stone center between April and December 2011. Radiation exposure measurements were determined by a thermoluminescent dosimeter worn on the outside of the surgeon's thyroid shield. Estimations of radiation exposure (mrem) per month were charted with fluoroscopy times, using scatter plots to estimate Spearman's rank correlation coefficients. Results: the total 9-month radiation exposure was 87 mrems for deep dose equivalent (DDE), 293 mrem for lens dose equivalent (LDE), and 282 mrem for shallow dose equivalent (SDE). Total fluoroscopy time was 252.44 minutes for 64 ureteroscopies (URSs), 29 percutaneous nephrolithtomies (PNLs), 20 cystoscopies with ureteral stent placements, 9 shock wave ithotripsies (SWLs), 9 retrograde pyelograms (RPGs), 2 endoureterotomies, and 1 ureteral balloon dilation. Spearman's rank correlation coefficients examining the association between fluoroscopy time and radiation exposure were not significant for DDE (p = 0.6, Spearman's rho = 0.2), LDE (p = 0.6, Spearman's rho = 0.2), or SDE (p = 0.6, Spearman's rho = 0.2). Conclusions: Over a 9-month period, total radiation exposures were well below annual accepted limits (DDE 5000 mrem, LDE 15,000 mrem and SDE 50,000 mrem). Although fluoroscopy time did not correlate with radiation exposure, future prospective studies can account for co-variates such as patient obesity and urologist distance from radiation source. (author)

  10. Standardized Semantic Markup for Reference Terminologies, Thesauri and Coding Systems: Benefits for distributed E-Health Applications.

    Science.gov (United States)

    Hoelzer, Simon; Schweiger, Ralf K; Liu, Raymond; Rudolf, Dirk; Rieger, Joerg; Dudeck, Joachim

    2005-01-01

    With the introduction of the ICD-10 as the standard for diagnosis, the development of an electronic representation of its complete content, inherent semantics and coding rules is necessary. Our concept refers to current efforts of the CEN/TC 251 to establish a European standard for hierarchical classification systems in healthcare. We have developed an electronic representation of the ICD-10 with the extensible Markup Language (XML) that facilitates the integration in current information systems or coding software taking into account different languages and versions. In this context, XML offers a complete framework of related technologies and standard tools for processing that helps to develop interoperable applications.

  11. Measurement of strontium-89 and strontium-90 in environmental waters. A tentative reference method

    International Nuclear Information System (INIS)

    1976-03-01

    A tentative reference method for the measurement of 89 Sr and 90 Sr in environmental waters is described. Samples of environmental water sources are collected, preserved with acid-strontium carrier, and analyzed for 89 Sr and/or 90 Sr. The isotopes are separated from the sample water by precipitating with stable strontium carrier as carbonate. The strontium carbonate is dissolved, 90 Sr separated, the strontium reprecipitated as carbonate, filtered, and counted for the combined 89 Sr and 90 Sr activity. The 90 y is allowed to grow in from the 90 y activity; the strontium carbonate is redissolved; the 90 y is separated, precipitated, and counted for the 90 Sr determination. The 89 Sr activity is then determined by difference of the total 89 Sr and 90 y and the separate 90 Sr activities. Recoveries are determined from the added and found (recovered) strontium carrier. Counting efficiencies are determined with prepared standard reference samples. Results are reported in pCi/liter

  12. Standard test method for isotopic analysis of uranium hexafluoride by double standard single-collector gas mass spectrometer method

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This is a quantitative test method applicable to determining the mass percent of uranium isotopes in uranium hexafluoride (UF6) samples with 235U concentrations between 0.1 and 5.0 mass %. 1.2 This test method may be applicable for the entire range of 235U concentrations for which adequate standards are available. 1.3 This test method is for analysis by a gas magnetic sector mass spectrometer with a single collector using interpolation to determine the isotopic concentration of an unknown sample between two characterized UF6 standards. 1.4 This test method is to replace the existing test method currently published in Test Methods C761 and is used in the nuclear fuel cycle for UF6 isotopic analyses. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appro...

  13. Comparison of US Birth Weight References and the International Fetal and Newborn Growth Consortium for the 21st Century Standard

    DEFF Research Database (Denmark)

    Kozuki, Naoko; Katz, Joanne; Christian, Parul

    2015-01-01

    ) status. OBJECTIVES: To compare the birth weight distributions of the INTERGROWTH-21st international standard to commonly used US references and examine the differences in the prevalence and neonatal mortality risk of SGA status (below the 10th percentile of a population reference). DESIGN, SETTING...... variance. MAIN OUTCOMES AND MEASURES: We examine neonatal mortality (death within the first 28 days after birth) as the main outcome measure. RESULTS: The pooled SGA prevalence was 23.7% (95% CI, 16.5%-31.0%) using the INTERGROWTH-21st standard compared with 36.0% (95% CI, 27.0%-45.0%) with the US 2000...... and no significant change in the associated neonatal mortality risk, resulting in a decrease in the percentage of neonatal death attributable to SGA. Our study sheds light on how previously published studies on SGA status may be reinterpreted with the introduction of this new birth weight standard....

  14. Technical Note: Modification of the standard gain correction algorithm to compensate for the number of used reference flat frames in detector performance studies

    International Nuclear Information System (INIS)

    Konstantinidis, Anastasios C.; Olivo, Alessandro; Speller, Robert D.

    2011-01-01

    Purpose: The x-ray performance evaluation of digital x-ray detectors is based on the calculation of the modulation transfer function (MTF), the noise power spectrum (NPS), and the resultant detective quantum efficiency (DQE). The flat images used for the extraction of the NPS should not contain any fixed pattern noise (FPN) to avoid contamination from nonstochastic processes. The ''gold standard'' method used for the reduction of the FPN (i.e., the different gain between pixels) in linear x-ray detectors is based on normalization with an average reference flat-field. However, the noise in the corrected image depends on the number of flat frames used for the average flat image. The aim of this study is to modify the standard gain correction algorithm to make it independent on the used reference flat frames. Methods: Many publications suggest the use of 10-16 reference flat frames, while other studies use higher numbers (e.g., 48 frames) to reduce the propagated noise from the average flat image. This study quantifies experimentally the effect of the number of used reference flat frames on the NPS and DQE values and appropriately modifies the gain correction algorithm to compensate for this effect. Results: It is shown that using the suggested gain correction algorithm a minimum number of reference flat frames (i.e., down to one frame) can be used to eliminate the FPN from the raw flat image. This saves computer memory and time during the x-ray performance evaluation. Conclusions: The authors show that the method presented in the study (a) leads to the maximum DQE value that one would have by using the conventional method and very large number of frames and (b) has been compared to an independent gain correction method based on the subtraction of flat-field images, leading to identical DQE values. They believe this provides robust validation of the proposed method.

  15. Method of making stepped photographic density standards of radiographic photographs

    International Nuclear Information System (INIS)

    Borovin, I.V.; Kondina, M.A.

    1987-01-01

    In industrial radiography practice the need often arises for a prompt evaluation of the photographic density of an x-ray film. A method of making stepped photographic density standards for industrial radiography by contact printing from a negative is described. The method is intended for industrial radiation flaw detection laboratories not having specialized sensitometric equipment

  16. SYSTEMATIC ERROR REDUCTION: NON-TILTED REFERENCE BEAM METHOD FOR LONG TRACE PROFILER

    International Nuclear Information System (INIS)

    QIAN, S.; QIAN, K.; HONG, Y.; SENG, L.; HO, T.; TAKACS, P.

    2007-01-01

    Systematic error in the Long Trace Profiler (LTP) has become the major error source as measurement accuracy enters the nanoradian and nanometer regime. Great efforts have been made to reduce the systematic error at a number of synchrotron radiation laboratories around the world. Generally, the LTP reference beam has to be tilted away from the optical axis in order to avoid fringe overlap between the sample and reference beams. However, a tilted reference beam will result in considerable systematic error due to optical system imperfections, which is difficult to correct. Six methods of implementing a non-tilted reference beam in the LTP are introduced: (1) application of an external precision angle device to measure and remove slide pitch error without a reference beam, (2) independent slide pitch test by use of not tilted reference beam, (3) non-tilted reference test combined with tilted sample, (4) penta-prism scanning mode without a reference beam correction, (5) non-tilted reference using a second optical head, and (6) alternate switching of data acquisition between the sample and reference beams. With a non-tilted reference method, the measurement accuracy can be improved significantly. Some measurement results are presented. Systematic error in the sample beam arm is not addressed in this paper and should be treated separately

  17. [Modified Delphi method in the constitution of school sanitation standard].

    Science.gov (United States)

    Yin, Xunqiang; Liang, Ying; Tan, Hongzhuan; Gong, Wenjie; Deng, Jing; Luo, Jiayou; Di, Xiaokang; Wu, Yue

    2012-11-01

    To constitute school sanitation standard using modified Delphi method, and to explore the feasibility and the predominance of Delphi method in the constitution of school sanitation standard. Two rounds of expert consultations were adopted in this study. The data were analyzed with SPSS15.0 to screen indices of school sanitation standard. Thirty-two experts accomplished the 2 rounds of consultations. The average length of expert service was (24.69 ±8.53) years. The authority coefficient was 0.729 ±0.172. The expert positive coefficient was 94.12% (32/34) in the first round and 100% (32/32) in the second round. The harmonious coefficients of importance, feasibility and rationality in the second round were 0.493 (PDelphi method is a rapid, effective and feasible method in this field.

  18. Dissemination of the National Standard of Mass from INACAL using the gauss Markov method by generalized least squares

    OpenAIRE

    Taipe, Donny

    2017-01-01

    This article sustains the transfer of the national standard of mass (KP1) of INACAL to two reference standards ‘Weight 1’, ‘Weight 2’ and also KP2 (as witnessed mass standard and with known error). The dissemination was done using the Gauss Markov method by Generalized Least Squares. The uncertainty calculation was performed using Univariate Gaussian Distribution and Multivariate Gaussian Distribution; the latter was developed with the Monte Carlo method using a programming language called 'R...

  19. Validation of the k0 standardization method in neutron activation analysis

    International Nuclear Information System (INIS)

    Kubesova, Marie

    2009-01-01

    The goal of this work was to validate the k 0 standardization method in neutron activation analysis for use by the Nuclear Physics Institute's NAA Laboratory. The precision and accuracy of the method were examined by using two types of reference materials: the one type comprised a set of synthetic materials and served to check the implementation of k 0 standardization, the other type consisted of matrix NIST SRMs comprising various different matrices. In general, a good agreement was obtained between the results of this work and the certified values, giving evidence of the accuracy of our results. In addition, the limits were evaluated for 61 elements

  20. Toward a standard method for determination of waterborne radon

    International Nuclear Information System (INIS)

    Vitz, E.

    1990-01-01

    When the USEPA specifies the maximum contaminant level (MCL) for any contaminant, a standard method for analysis must be simultaneously stipulated. Promulgation of the proposed MCL and standard method for radon in drinking water is expected by early next year, but a six-month comment period and revision will precede final enactment. The standard method for radon in drinking water will probably specify that either the Lucas cell technique or liquid scintillation spectrometry be used. This paper reports results which support a standard method with the following features: samples should be collected by an explicitly stated technique to control degassing, in glass vials with or without scintillation cocktail, and possibly in duplicate; samples should be measured by liquid scintillation spectroscopy in a specified energy window', in a glass vial with particular types of cocktails; radium standards should be prepared with controlled quench levels and specified levels of carriers, but radium-free controls prepared by a specified method should be used in interlaboratory comparison studies

  1. Polycyclic aromatic hydrocarbons (PAHs) in a coal tar standard reference material - SRM 1597a updated

    Energy Technology Data Exchange (ETDEWEB)

    Wise, Stephen A.; Poster, Dianne L.; Rimmer, Catherine A.; Schubert, Patricia; Sander, Lane C.; Schantz, Michele M. [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States); Leigh, Stefan D. [National Institute of Standards and Technology (NIST), Statistical Engineering Division, Gaithersburg, MD (United States); Moessner, Stephanie [National Institute of Standards and Technology (NIST), Analytical Chemistry Division, Gaithersburg, MD (United States); GMP/Comparator Labs, Werthenstein Chemie AG, Industrie Nord, Schachen (Switzerland)

    2010-09-15

    SRM 1597 Complex Mixture of Polycyclic Aromatic Hydrocarbons from Coal Tar, originally issued in 1987, was recently reanalyzed and reissued as SRM 1597a with 34 certified, 46 reference, and 12 information concentrations (as mass fractions) for polycyclic aromatic hydrocarbons (PAHs) and polycyclic aromatic sulfur heterocycles (PASHs) including methyl-substituted PAHs and PASHs. The certified and reference concentrations (as mass fractions) were based on results of analyses of the coal tar material using multiple analytical techniques including gas chromatography/mass spectrometry on four different stationary phases and reversed-phase liquid chromatography. SRM 1597a is currently the most extensively characterized SRM for PAHs and PASHs. (orig.)

  2. Standardized methods for photography in procedural dermatology using simple equipment.

    Science.gov (United States)

    Hexsel, Doris; Hexsel, Camile L; Dal'Forno, Taciana; Schilling de Souza, Juliana; Silva, Aline F; Siega, Carolina

    2017-04-01

    Photography is an important tool in dermatology. Reproducing the settings of before photos after interventions allows more accurate evaluation of treatment outcomes. In this article, we describe standardized methods and tips to obtain photographs, both for clinical practice and research procedural dermatology, using common equipment. Standards for the studio, cameras, photographer, patients, and framing are presented in this article. © 2017 The International Society of Dermatology.

  3. Standard Test Method for Abrasive Wear Resistance of Cemented

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the determination of abrasive wear resistance of cemented carbides. 1.2 The values stated in inch-pound units are to be regarded as the standard. The SI equivalents of inch-pound units are in parentheses and may be approximate. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  4. Design of a new torque standard machine based on a torque generation method using electromagnetic force

    International Nuclear Information System (INIS)

    Nishino, Atsuhiro; Ueda, Kazunaga; Fujii, Kenichi

    2017-01-01

    To allow the application of torque standards in various industries, we have been developing torque standard machines based on a lever deadweight system, i.e. a torque generation method using gravity. However, this method is not suitable for expanding the low end of the torque range, because of the limitations to the sizes of the weights and moment arms. In this study, the working principle of the torque generation method using an electromagnetic force was investigated by referring to watt balance experiments used for the redefinition of the kilogram. Applying this principle to a rotating coordinate system, an electromagnetic force type torque standard machine was designed and prototyped. It was experimentally demonstrated that SI-traceable torque could be generated by converting electrical power to mechanical power. Thus, for the first time, SI-traceable torque was successfully realized using a method other than that based on the force of gravity. (paper)

  5. Fathead minnows (Pimephales promelas) and goldfish (Carassius auratus) as standard fish in bioassays and their reaction to potential reference toxicants

    Energy Technology Data Exchange (ETDEWEB)

    Adelman, I.R.; Smith, L.L. Jr.

    1976-02-01

    Fathead minnows (Pimephales promelas) and goldfish (Carassius auratus) were compared for their suitability as standard bioassay fish. Both species showed the same variability of bioassay results when tested with four toxicants. Fathead minnows are recommended on the basis of their small size and on their capability for use in complete life cycle tests. On the basis of minimum variability of bioassay results, sodium chloride was superior for use as a reference toxicant. Both sodium chloride and pentachlorophenol seemed capable of detecting abnormal fish. On the basis of seven listed criteria either sodium chloride or pentachlorophenol would be acceptable as a reference toxicant.

  6. A New Synchronous Reference Frame-Based Method for Single-Phase Shunt Active Power Filters

    DEFF Research Database (Denmark)

    Monfared, Mohammad; Golestan, Saeed; Guerrero, Josep M.

    2013-01-01

    This paper deals with the design of a novel method in the synchronous reference frame (SRF) to extract the reference compensating current for single-phase shunt active power filters (APFs). Unlike previous works in the SRF, the proposed method has an innovative feature that it does not need...... the fictitious current signal. Frequency-independent operation, accurate reference current extraction and relatively fast transient response are other key features of the presented strategy. The effectiveness of the proposed method is investigated by means of detailed mathematical analysis. The results confirm...

  7. Statistical benchmarking in utility regulation: Role, standards and methods

    International Nuclear Information System (INIS)

    Newton Lowry, Mark; Getachew, Lullit

    2009-01-01

    Statistical benchmarking is being used with increasing frequency around the world in utility rate regulation. We discuss how and where benchmarking is in use for this purpose and the pros and cons of regulatory benchmarking. We then discuss alternative performance standards and benchmarking methods in regulatory applications. We use these to propose guidelines for the appropriate use of benchmarking in the rate setting process. The standards, which we term the competitive market and frontier paradigms, have a bearing on method selection. These along with regulatory experience suggest that benchmarking can either be used for prudence review in regulation or to establish rates or rate setting mechanisms directly

  8. Improving Reference Service: The Case for Using a Continuous Quality Improvement Method.

    Science.gov (United States)

    Aluri, Rao

    1993-01-01

    Discusses the evaluation of library reference service; examines problems with past evaluations, including the lack of long-term planning and a systems perspective; and suggests a method for continuously monitoring and improving reference service using quality improvement tools such as checklists, cause and effect diagrams, Pareto charts, and…

  9. Resampling methods in Microsoft Excel® for estimating reference intervals.

    Science.gov (United States)

    Theodorsson, Elvar

    2015-01-01

    Computer-intensive resampling/bootstrap methods are feasible when calculating reference intervals from non-Gaussian or small reference samples. Microsoft Excel® in version 2010 or later includes natural functions, which lend themselves well to this purpose including recommended interpolation procedures for estimating 2.5 and 97.5 percentiles. 
The purpose of this paper is to introduce the reader to resampling estimation techniques in general and in using Microsoft Excel® 2010 for the purpose of estimating reference intervals in particular.
 Parametric methods are preferable to resampling methods when the distributions of observations in the reference samples is Gaussian or can transformed to that distribution even when the number of reference samples is less than 120. Resampling methods are appropriate when the distribution of data from the reference samples is non-Gaussian and in case the number of reference individuals and corresponding samples are in the order of 40. At least 500-1000 random samples with replacement should be taken from the results of measurement of the reference samples.

  10. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. 801.7 Section 801.7 Agriculture Regulations of the Department of Agriculture...), DEPARTMENT OF AGRICULTURE OFFICIAL PERFORMANCE REQUIREMENTS FOR GRAIN INSPECTION EQUIPMENT § 801.7 Reference...

  11. Uncertainty Analysis of Spectral Irradiance Reference Standards Used for NREL Calibrations

    Energy Technology Data Exchange (ETDEWEB)

    Habte, A.; Andreas, A.; Reda, I.; Campanelli, M.; Stoffel, T.

    2013-05-01

    Spectral irradiance produced by lamp standards such as the National Institute of Standards and Technology (NIST) FEL-type tungsten halogen lamps are used to calibrate spectroradiometers at the National Renewable Energy Laboratory. Spectroradiometers are often used to characterize spectral irradiance of solar simulators, which in turn are used to characterize photovoltaic device performance, e.g., power output and spectral response. Therefore, quantifying the calibration uncertainty of spectroradiometers is critical to understanding photovoltaic system performance. In this study, we attempted to reproduce the NIST-reported input variables, including the calibration uncertainty in spectral irradiance for a standard NIST lamp, and quantify uncertainty for measurement setup at the Optical Metrology Laboratory at the National Renewable Energy Laboratory.

  12. NASA/NBS (National Aeronautics and Space Administration/National Bureau of Standards) standard reference model for telerobot control system architecture (NASREM)

    Science.gov (United States)

    Albus, James S.; Mccain, Harry G.; Lumia, Ronald

    1989-01-01

    The document describes the NASA Standard Reference Model (NASREM) Architecture for the Space Station Telerobot Control System. It defines the functional requirements and high level specifications of the control system for the NASA space Station document for the functional specification, and a guideline for the development of the control system architecture, of the 10C Flight Telerobot Servicer. The NASREM telerobot control system architecture defines a set of standard modules and interfaces which facilitates software design, development, validation, and test, and make possible the integration of telerobotics software from a wide variety of sources. Standard interfaces also provide the software hooks necessary to incrementally upgrade future Flight Telerobot Systems as new capabilities develop in computer science, robotics, and autonomous system control.

  13. Standard Test Method for Thermal Oxidative Resistance of Carbon Fibers

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1982-01-01

    1.1 This test method covers the apparatus and procedure for the determination of the weight loss of carbon fibers, exposed to ambient hot air, as a means of characterizing their oxidative resistance. 1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units which are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard information, see Section 8.

  14. Standardization of Tc-99 by three liquid scintillation counting methods

    International Nuclear Information System (INIS)

    Wyngaardt, W.M. van; Staden, M.J. van; Lubbe, J.; Simpson, B.R.S.

    2014-01-01

    The NMISA participated in the international key comparison of the pure beta-emitter Technetium-99, CCRI(II)-K2.Tc-99. The comparison solution was standardized using three methods, namely the TDCR efficiency calculation method, the CIEMAT/NIST efficiency tracing method and the 4π(LS)β–γ coincidence tracing method with Co-60 as tracer. Excellent agreement between results obtained with the three methods confirmed the applicability of the beta spectral shape given by the latest (2011) DDEP evaluation of Tc-99 decay data, rather than the earlier (2004) evaluation. - Highlights: • Activity concentration of Tc-99 solution measured using three LSC methods. • Methods used are TDCR, CNET and 4π(LS)β–γ coincidence tracing. • Beta spectral shape confirmed by agreement between three methods

  15. Thermal conductivity and electrical resistivity standard reference materials: tungsten SRM's 730 and 799, from 4 to 30000K. Final report

    International Nuclear Information System (INIS)

    Hust, J.G.; Giarratano, P.J.

    1975-09-01

    A historical review of the development of thermophysical Standard Reference Materials, SRM's, is given and selection criteria of SRM's are listed. Thermal conductivity and electrical resistivity data for arc cast and sintered tungsten are compiled, analyzed, and correlated. Recommended values of thermal conductivity (SRM 730) and electrical resistivity (SRM 799) for these lots of tungsten are presented for the range 4 to 3000 0 K

  16. Safety evaluation report related to the preliminary design of the Standard Reference System, RESAR-414

    International Nuclear Information System (INIS)

    1978-11-01

    The safety evaluation for the Westinghouse Standard Reactor includes information on general reactor characteristics; design criteria for systems and components; reactor coolant system; engineered safety systems; instrumentation and controls; electric power systems; auxiliary systems; steam and power conversion system; radioactive waste management; radiation protection; conduct of operations; accident analyses; and quality assurance

  17. 77 FR 751 - Federal Motor Vehicle Safety Standards; Matters Incorporated by Reference

    Science.gov (United States)

    2012-01-06

    ... Recommended Practice J1133, ``School Bus Stop Arm,'' revised April 1984, into Sec. 571.131. (45) SAE Standard... constriction requirement of S5.3.1 after having been subjected to a temperature of 248 degrees Fahrenheit (120... mandatory requirements. * * * * * S6.4.5 School bus signal lamp aiming. Each school bus signal lamp must be...

  18. 75 FR 48593 - Pipeline Safety: Periodic Updates of Regulatory References to Technical Standards and...

    Science.gov (United States)

    2010-08-11

    ... (ASTM): ASTM A53/A53M-07 (2007), ``Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless'' (September 1, 2007). Replaces IBR: 2004 edition; Referenced in 49 CFR 192...), we clarify that cast iron, malleable iron, or ductile iron may be used in the valve ball or plug...

  19. Robust steganographic method utilizing properties of MJPEG compression standard

    Directory of Open Access Journals (Sweden)

    Jakub Oravec

    2015-06-01

    Full Text Available This article presents design of steganographic method, which uses video container as cover data. Video track was recorded by webcam and was further encoded by compression standard MJPEG. Proposed method also takes in account effects of lossy compression. The embedding process is realized by switching places of transform coefficients, which are computed by Discrete Cosine Transform. The article contains possibilities, used techniques, advantages and drawbacks of chosen solution. The results are presented at the end of the article.

  20. Standard methods for rearing and selection of Apis mellifera queens

    DEFF Research Database (Denmark)

    Büchler, Ralph; Andonov, Sreten; Bienefeld, Kaspar

    2013-01-01

    Here we cover a wide range of methods currently in use and recommended in modern queen rearing, selection and breeding. The recommendations are meant to equally serve as standards for both scientific and practical beekeeping purposes. The basic conditions and different management techniques for q...

  1. Standard test method for dynamic tear testing of metallic materials

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1983-01-01

    1.1 This test method covers the dynamic tear (DT) test using specimens that are 3/16 in. to 5/8 in. (5 mm to 16 mm) inclusive in thickness. 1.2 This test method is applicable to materials with a minimum thickness of 3/16 in. (5 mm). 1.3 The pressed-knife procedure described for sharpening the notch tip generally limits this test method to materials with a hardness level less than 36 HRC. Note 1—The designation 36 HRC is a Rockwell hardness number of 36 on Rockwell C scale as defined in Test Methods E 18. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  2. Evaluating the Capacity of Standard Investment Appraisal Methods

    NARCIS (Netherlands)

    M.M. Akalu

    2002-01-01

    textabstractThe survey findings indicate the existence of gap between theory and practice of capital budgeting. Standard appraisal methods have shown a wider project value discrepancy, which is beyond and above the contingency limit. In addition, the research has found the growing trend in the use

  3. Determinants of teenage smoking, with special reference to non-standard family background.

    Science.gov (United States)

    Isohanni, M; Moilanen, I; Rantakallio, P

    1991-04-01

    The prevalence of teenage smoking in a cohort of 12,058 subjects born in northern Finland in 1966 is discussed in terms of its social and family determinants, especially in "non-standard" families (with one or more of the parents absent for at least part of the child's upbringing). The prevalence of experimental or daily smoking was 67.4%, the rate being 65.5% in the standard, two-parent families and 75.5% in the non-standard families, the difference being statistically significant (p less than 0.001). The corresponding prevalence of daily smoking was 6.4%, but the rate was 5.1% in standard families and 12.1% in non-standard families (p less than 0.001). An elevated risk of smoking existed among adolescents who had experienced death of their father or divorce of their parents and among girls who had experienced death of their mother. Maternal smoking during pregnancy and maternal age under 20 years at the time of delivery increased the risk, while being the first-born child reduced it. Among family factors existing in 1980, paternal smoking increased the risk for both sexes, while more than three siblings, mother's unemployment or gainful employment (i.e. not a housewife) were associated with smoking by the boys as was urban living, and for the girls migration by the family to a town. The results suggest that juvenile smoking may be a kind of indicator of possible problems experienced by the parents and/or the adolescents themselves with respect to parenthood and family development.

  4. Official ERS technical standards: Global Lung Function Initiative reference values for the carbon monoxide transfer factor for Caucasians.

    Science.gov (United States)

    Stanojevic, Sanja; Graham, Brian L; Cooper, Brendan G; Thompson, Bruce R; Carter, Kim W; Francis, Richard W; Hall, Graham L

    2017-09-01

    There are numerous reference equations available for the single-breath transfer factor of the lung for carbon monoxide ( T  LCO ); however, it is not always clear which reference set should be used in clinical practice. The aim of the study was to develop the Global Lung Function Initiative (GLI) all-age reference values for T  LCO Data from 19 centres in 14 countries were collected to define T  LCO reference values. Similar to the GLI spirometry project, reference values were derived using the LMS (lambda, mu, sigma) method and the GAMLSS (generalised additive models for location, scale and shape) programme in R.12 660 T  LCO measurements from asymptomatic, lifetime nonsmokers were submitted; 85% of the submitted data were from Caucasians. All data were uncorrected for haemoglobin concentration. Following adjustments for elevation above sea level, gas concentration and assumptions used for calculating the anatomic dead space volume, there was a high degree of overlap between the datasets. Reference values for Caucasians aged 5-85 years were derived for T  LCO , transfer coefficient of the lung for carbon monoxide and alveolar volume.This is the largest collection of normative T  LCO data, and the first global reference values available for T  LCO . Copyright ©ERS 2017.

  5. 75 FR 22126 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Science.gov (United States)

    2010-04-27

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9142-1] Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of one new equivalent method for monitoring ambient air...

  6. 75 FR 9894 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Science.gov (United States)

    2010-03-04

    ..., Research Triangle Park, North Carolina 27711. Designation of this new equivalent method is intended to... ENVIRONMENTAL PROTECTION AGENCY [FRL-9121-6] Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of One New Equivalent Method AGENCY: Environmental...

  7. 76 FR 15974 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Science.gov (United States)

    2011-03-22

    ..., Research Triangle Park, North Carolina 27711. Designation of these new equivalent methods is intended to... ENVIRONMENTAL PROTECTION AGENCY [FRL-9285-2] Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of Four New Equivalent Methods AGENCY: Environmental...

  8. 76 FR 62402 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Science.gov (United States)

    2011-10-07

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9476-7] Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods; Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of one new equivalent method for monitoring ambient air...

  9. 75 FR 51039 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Science.gov (United States)

    2010-08-18

    ..., Research Triangle Park, North Carolina 27711. Designation of these new equivalent methods is intended to... ENVIRONMENTAL PROTECTION AGENCY [FRL-9190-5] Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of Two New Equivalent Methods AGENCY: Environmental...

  10. 75 FR 30022 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Science.gov (United States)

    2010-05-28

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9156-1] Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of one new equivalent method for monitoring ambient air...

  11. Normalization Methods and Selection Strategies for Reference Materials in Stable Isotope Analyes. Review

    Energy Technology Data Exchange (ETDEWEB)

    Skrzypek, G. [West Australian Biogeochemistry Centre, John de Laeter Centre of Mass Spectrometry, School of Plant Biology, University of Western Australia, Crawley (Australia); Sadler, R. [School of Agricultural and Resource Economics, University of Western Australia, Crawley (Australia); Paul, D. [Department of Civil Engineering (Geosciences), Indian Institute of Technology Kanpur, Kanpur (India); Forizs, I. [Institute for Geochemical Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-07-15

    Stable isotope ratio mass spectrometers are highly precise, but not accurate instruments. Therefore, results have to be normalized to one of the isotope scales (e.g., VSMOW, VPDB) based on well calibrated reference materials. The selection of reference materials, numbers of replicates, {delta}-values of these reference materials and normalization technique have been identified as crucial in determining the uncertainty associated with the final results. The most common normalization techniques and reference materials have been tested using both Monte Carlo simulations and laboratory experiments to investigate aspects of error propagation during the normalization of isotope data. The range of observed differences justifies the need to employ the same sets of standards worldwide for each element and each stable isotope analytical technique. (author)

  12. Reference Material Properties and Standard Problems to Verify the Fuel Performance Models Ver 1.0

    International Nuclear Information System (INIS)

    Yang, Yong Sik; Kim, Jae Yong; Koo, Yang Hyun

    2010-12-01

    All fuel performance models must be validated by in-pile and out-pile tests. However, the model validation requires much efforts and times to confirm its exactness. In many fields, new performance models and codes are confirmed by code-to-code benchmarking process under simplified standard problem analysis. At present, the DUOS, which is the steady state fuel performance analysis code for dual cooled annular fuel, development project is progressing and new FEM module is developed to analyze the fuel performance during transient period. In addition, the verification process is planning to examine the new models and module's rightness by comparing with commercial finite element analysis such as a ADINA, ABAQUS and ANSYS. This reports contains the result of unification of material properties and establishment of standard problem to verify the newly developed models with commercial FEM code

  13. Experimental validation of the buildings energy performance (PEC assessment methods with reference to occupied spaces heating

    Directory of Open Access Journals (Sweden)

    Cristian PETCU

    2010-01-01

    provided by measurements and to those provided by the monthly calculation (NP 048-2006. The deviations of 1.45% and 2.2% respectively validate the hourly calculation model, as they actually have no physical significance. The report presents a phenomenological analysis of the building transfer functions synthesized as tev (τ, functions which attest their phenomenological objectivity in macro and hourly terms. The case studies completing the calculation models experimental validation emphasize unacceptably large differences between the results provided by the use of standardized calculation methods (Mc 001 / 2-2006 and SR EN 13790:2009 and those specific to the methods referred to in this report, experimentally validated.

  14. Standard method for economic analyses of inertial confinement fusion power plants

    International Nuclear Information System (INIS)

    Meier, W.R.

    1986-01-01

    A standard method for calculating the total capital cost and the cost of electricity for a typical inertial confinement fusion electric power plant has been developed. A standard code of accounts at the two-digit level is given for the factors making up the total capital cost of the power plant. Equations are given for calculating the indirect capital costs, the project contingency, and the time-related costs. Expressions for calculating the fixed charge rate, which is necessary to determine the cost of electricity, are also described. Default parameters are given to define a reference case for comparative economic analyses

  15. Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    Science.gov (United States)

    Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

    2011-01-01

    oceanography. The other two salinity variables provide alternative measures of the mass fraction of dissolved material in seawater. "Solution Salinity", denoted SAsoln, is the most obvious extension of Reference Salinity to allow for composition anomalies; it provides a direct estimate of the mass fraction of dissolved material in solution. "Added-Mass Salinity", denoted SAadd, is motivated by a method used to report laboratory experiments; it represents the component of dissolved material added to Standard Seawater in terms of the mass of material before it enters solution. We also discuss a constructed conservative variable referred to as "Preformed Salinity", denoted S∗, which will be useful in process-oriented numerical modelling studies. Finally, a conceptual framework for the incorporation of composition anomalies in numerical models is presented that builds from studies in which composition anomalies are simply ignored up to studies in which the influences of composition anomalies are accounted for using the results of biogeochemical models. 1TEOS-10: international Thermodynamic Equation of Seawater 2010, http://www.teos-10.org/.

  16. Absolute Salinity, "Density Salinity" and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    Science.gov (United States)

    Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

    2010-08-01

    oceanography. The other two salinity variables provide alternative measures of the mass fraction of dissolved material in seawater. "Solution Salinity", denoted SAsoln, is the most obvious extension of Reference Salinity to allow for composition anomalies; it provides a direct estimate of the mass fraction of dissolved material in solution. "Added-Mass Salinity", denoted SAadd, is motivated by a method used to report laboratory experiments; it represents the component of dissolved material added to Standard Seawater in terms of the mass of material before it enters solution. We also discuss a constructed conservative variable referred to as "Preformed Salinity", denoted S*, which will be useful in process-oriented numerical modelling studies. Finally, a conceptual framework for the incorporation of composition anomalies in numerical models is presented that builds from studies in which composition anomalies are simply ignored up to studies in which the influences of composition anomalies are accounted for using the results of biogeochemical models. 1TEOS-10: international thermodynamic equation of seawater 2010, http://www.teos-10.org.

  17. Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    Directory of Open Access Journals (Sweden)

    D. G. Wright

    2011-01-01

    >SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical oceanography. The other two salinity variables provide alternative measures of the mass fraction of dissolved material in seawater. "Solution Salinity", denoted SAsoln, is the most obvious extension of Reference Salinity to allow for composition anomalies; it provides a direct estimate of the mass fraction of dissolved material in solution. "Added-Mass Salinity", denoted SAadd, is motivated by a method used to report laboratory experiments; it represents the component of dissolved material added to Standard Seawater in terms of the mass of material before it enters solution. We also discuss a constructed conservative variable referred to as "Preformed Salinity", denoted S, which will be useful in process-oriented numerical modelling studies.

    Finally, a conceptual framework for the incorporation of composition anomalies in numerical models is presented that builds from studies in which composition anomalies are simply ignored up to studies in which the influences of composition anomalies are accounted for using the results of biogeochemical models.

    1TEOS-10: international Thermodynamic Equation of Seawater 2010, http://www.teos-10.org/.

  18. Simultaneous determination of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in standard reference material baking chocolate 2384, cocoa, cocoa beans, and cocoa butter.

    Science.gov (United States)

    Risner, Charles H

    2008-01-01

    A reverse-phase liquid chromatography analysis is used to access the quantity of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in Standard Reference Material 2384 Baking Chocolate, cocoa, cocoa beans, and cocoa butter using water or a portion of the mobile phase as the extract. The procedure requires minimal sample preparation. Theobromine, (+)-catechin, caffeine, and (-)-epicatechin are detected by UV absorption at 273 nm after separation using a 0.3% acetic acid-methanol gradient (volume fractions) and quantified using external standards. The limit of detection for theobromine, (+)-catechin, caffeine, and (-)-epicatechin averages 0.08, 0.06, 0.06, and 0.06 microg/mL, respectively. The method when applied to Standard Reference Material 2384 Baking Chocolate; baking chocolate reference material yields results that compare to two different, separate procedures. Theobromine ranges from 26000 mg/kg in cocoa to 140 mg/kg in cocoa butter; (+)-catechin from 1800 mg/kg in cocoa to below detection limits of theobromine, 100.0 +/- 0.6 for (+)-catechin, 96.2 +/- 2.1 for caffeine, and 106.2 +/- 1.7 for (-)-epicatechin.

  19. The new fabrication method of standard surface sources

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yasushi E-mail: yss.sato@aist.go.jp; Hino, Yoshio; Yamada, Takahiro; Matsumoto, Mikio

    2004-04-01

    We developed a new fabrication method for standard surface sources by using an inkjet printer with inks in which a radioactive material is mixed to print on a sheet of paper. Three printed test patterns have been prepared: (1) 100 mmx100 mm uniformity-test patterns, (2) positional-resolution test patterns with different widths and intervals of straight lines, and (3) logarithmic intensity test patterns with different radioactive intensities. The results revealed that the fabricated standard surface sources had high uniformity, high positional resolution, arbitrary shapes and a broad intensity range.

  20. The application of the k0-standardization method at the TRIGA Mark II reactor, Ljubljana, Slovenia

    International Nuclear Information System (INIS)

    Jacimovic, Radojko; Benedik, Ljudmila; Stegnar, Peter; Smodis, Borut

    2002-01-01

    The k 0 -standardization method of neutron activation analysis (k 0 -NAA) was launched in the 1970s and since then continuously developed. Nowadays, k 0 -NAA became widespread as a practical analytical tool used to analyse different sample matrices. At the Jozef Stefan Institute (IJS), the KAYZERO/SOLCOI software package has been introduced for data processing after extensive testing and comparison with other available programs. In the process of validation of the software a suite of natural matrix reference materials (RMs) were used. Five certified reference materials (CRMs) from the Institute for Reference Materials and Measurements (IRMM), two standard reference materials (SRMs) from the National Institute of Standards and Technology (NIST), three RMs from the International Atomic Energy Agency (IAEA) and one RM from IJS were analysed. Altogether, results for ten elements in inorganic matrices and twenty-one elements in organic matrices, obtained by k 0 -instrumental neutron activation analysis (k 0 -INAA), were compared to certified values. The results obtained show good agreement with certified or assigned values except for Fe and U in inorganic matrices, and Al and Cr in organic matrices. (author)

  1. The uncertainty of reference standards--a guide to understanding factors impacting uncertainty, uncertainty calculations, and vendor certifications.

    Science.gov (United States)

    Gates, Kevin; Chang, Ning; Dilek, Isil; Jian, Huahua; Pogue, Sherri; Sreenivasan, Uma

    2009-10-01

    Certified solution standards are widely used in forensic toxicological, clinical/diagnostic, and environmental testing. Typically, these standards are purchased as ampouled solutions with a certified concentration. Vendors present concentration and uncertainty differently on their Certificates of Analysis. Understanding the factors that impact uncertainty and which factors have been considered in the vendor's assignment of uncertainty are critical to understanding the accuracy of the standard and the impact on testing results. Understanding these variables is also important for laboratories seeking to comply with ISO/IEC 17025 requirements and for those preparing reference solutions from neat materials at the bench. The impact of uncertainty associated with the neat material purity (including residual water, residual solvent, and inorganic content), mass measurement (weighing techniques), and solvent addition (solution density) on the overall uncertainty of the certified concentration is described along with uncertainty calculations.

  2. Determinations of elements in pepperbush standard reference material by neutron activation and X-ray fluorescence analyses

    International Nuclear Information System (INIS)

    Mizumoto, Yoshihiko; Okada, Takayuki; Tatsumi, Toshiya; Kusakabe, Toshio; Katsurayama, Kousuke; Iwata, Shiro.

    1988-01-01

    Elemental contents in Pepperbush standard reference material have been determined by neutron activation and X-ray fluorescence analyses. The standard samples of orchard leaves, tomato leaves, pine needles and Kale are used for the experiment. In the neutron activation analysis, gamma-ray spectra of nuclei produced by (n,γ) reaction on Pepperbush and standard samples are measured with Ge detectors. In the X-ray fluorescence analysis, the samples are excited with X-rays from X-ray tube with rhodium anode, and the characteristic X-rays from samples are measured with a proportional counter or NaI(Tl) detector. From the gamma- and X-ray intensities, the elemental contents in Pepperbush are determined. As a result, the contents of seventeen elements, such as sodium, calcium, iron, etc., in Pepperbush are determined. (author)

  3. Differences in serum thyroglobulin measurements by 3 commercial immunoradiometric assay kits and laboratory standardization using Certified Reference Material 457 (CRM-457).

    Science.gov (United States)

    Lee, Ji In; Kim, Ji Young; Choi, Joon Young; Kim, Hee Kyung; Jang, Hye Won; Hur, Kyu Yeon; Kim, Jae Hyeon; Kim, Kwang-Won; Chung, Jae Hoon; Kim, Sun Wook

    2010-09-01

    Serum thyroglobulin (Tg) is essential in the follow-up of patients with differentiated thyroid carcinoma (DTC). However, interchangeability and standardization between Tg assays have not yet been achieved, even with the development of an international Tg standard (Certified Reference Material 457 [CRM-457]). Serum Tg from 30 DTC patients and serially diluted CRM-457 were measured using 3 different immunoradiometric assays (IRMA-1, IRMA-2, IRMA-3). The intraclass correlation coefficient (ICC) method was used to describe the concordance of each IRMA to CRM-457. The serum Tg measured by 3 different IRMAs correlated well (r > .85, p CRM-457, showed the best ICC (p(1) = .98) for the CRM-457. Hospitals caring for patients with DTC should either set their own cutoffs for IRMAs for Tg based on their patient pools, or adopt IRMAs standardized to CRM-457 and calibrate their laboratory using CRM-457.

  4. A contemporary Colombian skeletal reference collection: A resource for the development of population specific standards.

    Science.gov (United States)

    Sanabria-Medina, Cesar; González-Colmenares, Gretel; Restrepo, Hadaluz Osorio; Rodríguez, Juan Manuel Guerrero

    2016-09-01

    Several authors who have discussed human variability and its impact on the forensic identification of bodies pose the need for regional studies documenting the global variation of the attributes analyzed osteological characteristics that aid in establishing biological profile (sex, ancestry, biological age and height). This is primarily accomplished by studying documented human skeletal collections in order to investigate secular trends in skeletal development and aging, among others in the Colombian population. The purpose of this paper is to disclose the details of the new "Contemporary Colombian Skeletal Reference Collection" that currently comprises 600 identified skeletons of both sexes, who died between 2005 and 2008; and which contain information about their cause of death. This collection has infinite potential for research, open to the national and international community, and still has pending opportunities to address a variety of topics such as studies on osteopathology, bone trauma and taphonomic studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for ultrasonic test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This practice facilitates the interoperability of ultrasonic imaging equipment by specifying image data transfer and archival storage methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E 2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E 2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, transfer and archival storage. The goal of Practice E 2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE test results on any system conforming to the DICONDE standard. Toward that end, Practice E 2339 provides a data dictionary and set of information modules that are applicable to all NDE modalities. This practice supplements Practice E 2339 by providing information object definitions, information ...

  6. Standard practice for digital imaging and communication nondestructive evaluation (DICONDE) for computed radiography (CR) test methods

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This practice facilitates the interoperability of computed radiography (CR) imaging and data acquisition equipment by specifying image data transfer and archival storage methods in commonly accepted terms. This practice is intended to be used in conjunction with Practice E2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, storage and archival storage. The goal of Practice E2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE results on any system conforming to the DICONDE standard. Toward that end, Practice E2339 provides a data dictionary and a set of information modules that are applicable to all NDE modalities. This practice supplements Practice E2339 by providing information objec...

  7. Standard test method for measurement of corrosion potentials of Aluminum alloys

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This test method covers a procedure for measurement of the corrosion potential (see Note 1) of an aluminum alloy in an aqueous solution of sodium chloride with enough hydrogen peroxide added to provide an ample supply of cathodic reactant. Note 1—The corrosion potential is sometimes referred to as the open-circuit solution or rest potential. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  8. Effect of reference loads on fracture mechanics analysis of surface cracked pipe based on reference stress method

    International Nuclear Information System (INIS)

    Shim, Do Jun; Son, Beom Goo; Kim, Young Jin; Kim, Yun Jae

    2004-01-01

    To investigate relevance of the definition of the reference stress to estimate J and C * for surface crack problems, this paper compares FE J and C * results for surface cracked pipes with those estimated according to the reference stress approach using various definitions of the reference stress. Pipes with part circumferential inner surface crack and finite internal axial crack are considered, subject to internal pressure and global bending. The crack depth and aspect ratio are systematically varied. The reference stress is defined in four different ways using (I) the local limit load, (II) the global limit load, (III) the global limit load determined from the FE limit analysis, and (IV) the optimised reference load. It is found that the reference stress based on the local limit load gives overall excessively conservative estimates of J and C * . Use of the global limit load clearly reduces the conservatism, compared to that of the local limit load, although it can provide sometimes non-conservative estimates of J and C * . The use of the FE global limit load gives overall non-conservative estimates of J and C * . The reference stress based on the optimised reference load gives overall accurate estimates of J and C * , compared to other definitions of the reference stress. Based on the present finding, general guidance on the choice of the reference stress for surface crack problems is given

  9. A self-reference PRF-shift MR thermometry method utilizing the phase gradient

    International Nuclear Information System (INIS)

    Langley, Jason; Potter, William; Phipps, Corey; Zhao Qun; Huang Feng

    2011-01-01

    In magnetic resonance (MR) imaging, the most widely used and accurate method for measuring temperature is based on the shift in proton resonance frequency (PRF). However, inter-scan motion and bulk magnetic field shifts can lead to inaccurate temperature measurements in the PRF-shift MR thermometry method. The self-reference PRF-shift MR thermometry method was introduced to overcome such problems by deriving a reference image from the heated or treated image, and approximates the reference phase map with low-order polynomial functions. In this note, a new approach is presented to calculate the baseline phase map in self-reference PRF-shift MR thermometry. The proposed method utilizes the phase gradient to remove the phase unwrapping step inherent to other self-reference PRF-shift MR thermometry methods. The performance of the proposed method was evaluated using numerical simulations with temperature distributions following a two-dimensional Gaussian function as well as phantom and in vivo experimental data sets. The results from both the numerical simulations and experimental data show that the proposed method is a promising technique for measuring temperature. (note)

  10. In-situ calibration of clinical built-in KAP meters with traceability to a primary standard using a reference KAP meter.

    Science.gov (United States)

    Malusek, A; Helmrot, E; Sandborg, M; Grindborg, J-E; Carlsson, G Alm

    2014-12-07

    The air kerma-area product (KAP) is used for settings of diagnostic reference levels. The International Atomic Energy Agency (IAEA) recommends that doses in diagnostic radiology (including the KAP values) be estimated with an accuracy of at least ± 7% (k = 2). Industry standards defined by the International Electrotechnical Commission (IEC) specify that the uncertainty of KAP meter measurements should be less than ± 25% (k = 2). Medical physicists willing to comply with the IAEA's recommendation need to apply correction factors to KAP values reported by x-ray units. The aim of this work is to present and evaluate a calibration method for built-in KAP meters on clinical x-ray units. The method is based on (i) a tandem calibration method, which uses a reference KAP meter calibrated to measure the incident radiation, (ii) measurements using an energy-independent ionization chamber to correct for the energy dependence of the reference KAP meter, and (iii) Monte Carlo simulations of the beam quality correction factors that correct for differences between beam qualities at a standard laboratory and the clinic. The method was applied to the KAP meter in a Siemens Aristos FX plus unit. It was found that values reported by the built-in KAP meter differed from the more accurate values measured by the reference KAP meter by more than 25% for high tube voltages (more than 140 kV) and heavily filtered beams (0.3 mm Cu). Associated uncertainties were too high to claim that the IEC's limit of 25% was exceeded. Nevertheless the differences were high enough to justify the need for a more accurate calibration of built-in KAP meters.

  11. Impact of a product-specific reference standard for the measurement of a PEGylated rFVIII activity: the Swiss Multicentre Field Study.

    Science.gov (United States)

    Bulla, O; Poncet, A; Alberio, L; Asmis, L M; Gähler, A; Graf, L; Nagler, M; Studt, J-D; Tsakiris, D A; Fontana, P

    2017-07-01

    Measuring factor VIII (FVIII) activity can be challenging when it has been modified, such as when FVIII is pegylated to increase its circulating half-life. Use of a product-specific reference standard may help avoid this issue. Evaluate the impact of using a product-specific reference standard for measuring the FVIII activity of BAX 855 - a pegylated FVIII - in eight of Switzerland's main laboratories. Factor VIII-deficient plasma, spiked with five different concentrations of BAX 855, plus a control FVIII sample, was sent to the participating laboratories. They measured FVIII activity by using either with a one-stage (OSA) or the chromogenic assay (CA) against their local or a product-specific reference standard. When using a local reference standard, there was an overestimation of BAX 855 activity compared to the target concentrations, both with the OSA and CA. The use of a product-specific reference standard reduced this effect: mean recovery ranged from 127.7% to 213.5% using the OSA with local reference standards, compared to 110% to 183.8% with a product-specific reference standard, and from 146.3% to 182.4% using the CA with local reference standards compared to 72.7% to 103.7% with a product-specific reference standard. In this in vitro study, the type of reference standard had a major impact on the measurement of BAX 855 activity. Evaluation was more accurate and precise when using a product-specific reference standard. © 2017 John Wiley & Sons Ltd.

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

    Science.gov (United States)

    Scharf, Holger; Bremser, Wolfram

    2015-04-01

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

  13. Design and realization of the high-precision weighing systems as the gravimetric references in PTB's national water flow standard

    International Nuclear Information System (INIS)

    Engel, Rainer; Beyer, Karlheinz; Baade, Hans-Joachim

    2012-01-01

    PTB's ‘Hydrodynamic Test Field’, which represents a high-accuracy water flow calibration facility, serves as the national primary standard for liquid flow measurands. As the core reference device of this flow facility, a gravimetric standard has been incorporated, which comprises three special-design weighing systems: 300 kg, 3 tons and 30 tons. These gravimetric references were realized as a combination of a strain-gauge-based and an electromagnetic-force-compensation load-cell-based balance, each. Special emphasis had to be placed upon the dynamics design of the whole weighing system, due to the high measurement resolution and the dynamic behavior of the weighing systems, which are dynamically affected by mechanical vibrations caused by environmental impacts, flow machinery operation, flow noise in the pipework and induced wave motions in the weigh tanks. Taking into account all the above boundary conditions, the design work for the gravimetric reference resulted in a concrete foundation ‘rock’ of some 300 tons that rests on a number of vibration isolators. In addition to these passively operating vibration isolators, the vibration damping effect is enhanced by applying an electronic level regulation device. (paper)

  14. Body mass index in Saudi Arabian children and adolescents: A national reference and comparison with international standards

    International Nuclear Information System (INIS)

    Al Herbish, Abdullah S; ElMouzan, Mohammed I; AlSalloum, Abdullah A; AlQureshi, Mansour M; AlOmar, Ahmed A; Fster, Peter J; Kecojevic, Tatjana

    2009-01-01

    Because there are no reference standards for body mass index (BMI) in Saudi children, we established BMI reference percentiles for normal Saudi Arabian children and adolescents and compared them with international standards. Data from a stratified multistage probability sample were collected from the 13 health regions in Saudi Arabia, as part of a nationwide health profile survey of Saudi Arabian children and adolescents conducted to establish normal physical growth references. Selected households were visited by a trained team. Weight and length/height were measured and recorded following the WHO recommended procedures using the same equipment, which were subjected to both calibration and intra/interobserver variations. Survey of 11 874 eligible households yielded 35 275 full-term and healthy children and adolescents who were subjected to anthropometric measurements. Four BMI curves were produced, from birth to 36 months and 2 to 19 years for girls and boys. The 3rd, 5th, 10th ,25th , 5oth , 75th ,85th , 90th , 95th , and 97th percentiles were produced and compared with the WHO and CDC BMI charts. In the higher percentiles, the Saudi children differed from Western counterparts, indicating that Saudi children have equal or higher BMIs. The BMI curves reflect statistically representative BMI values for Saudi Arabian children and adolescents. (author)

  15. High-resolution global grids of revised Priestley-Taylor and Hargreaves-Samani coefficients for assessing ASCE-standardized reference crop evapotranspiration and solar radiation

    Science.gov (United States)

    Aschonitis, Vassilis G.; Papamichail, Dimitris; Demertzi, Kleoniki; Colombani, Nicolo; Mastrocicco, Micol; Ghirardini, Andrea; Castaldelli, Giuseppe; Fano, Elisa-Anna

    2017-08-01

    The objective of the study is to provide global grids (0.5°) of revised annual coefficients for the Priestley-Taylor (P-T) and Hargreaves-Samani (H-S) evapotranspiration methods after calibration based on the ASCE (American Society of Civil Engineers)-standardized Penman-Monteith method (the ASCE method includes two reference crops: short-clipped grass and tall alfalfa). The analysis also includes the development of a global grid of revised annual coefficients for solar radiation (Rs) estimations using the respective Rs formula of H-S. The analysis was based on global gridded climatic data of the period 1950-2000. The method for deriving annual coefficients of the P-T and H-S methods was based on partial weighted averages (PWAs) of their mean monthly values. This method estimates the annual values considering the amplitude of the parameter under investigation (ETo and Rs) giving more weight to the monthly coefficients of the months with higher ETo values (or Rs values for the case of the H-S radiation formula). The method also eliminates the effect of unreasonably high or low monthly coefficients that may occur during periods where ETo and Rs fall below a specific threshold. The new coefficients were validated based on data from 140 stations located in various climatic zones of the USA and Australia with expanded observations up to 2016. The validation procedure for ETo estimations of the short reference crop showed that the P-T and H-S methods with the new revised coefficients outperformed the standard methods reducing the estimated root mean square error (RMSE) in ETo values by 40 and 25 %, respectively. The estimations of Rs using the H-S formula with revised coefficients reduced the RMSE by 28 % in comparison to the standard H-S formula. Finally, a raster database was built consisting of (a) global maps for the mean monthly ETo values estimated by ASCE-standardized method for both reference crops, (b) global maps for the revised annual coefficients of the P

  16. A Proposal of New Reference System for the Standard Axial, Sagittal, Coronal Planes of Brain Based on the Serially-Sectioned Images

    Science.gov (United States)

    Park, Jin Seo; Park, Hyo Seok; Shin, Dong Sun; Har, Dong-Hwan; Cho, Zang-Hee; Kim, Young-Bo; Han, Jae-Yong; Chi, Je-Geun

    2010-01-01

    Sectional anatomy of human brain is useful to examine the diseased brain as well as normal brain. However, intracerebral reference points for the axial, sagittal, and coronal planes of brain have not been standardized in anatomical sections or radiological images. We made 2,343 serially-sectioned images of a cadaver head with 0.1 mm intervals, 0.1 mm pixel size, and 48 bit color and obtained axial, sagittal, and coronal images based on the proposed reference system. This reference system consists of one principal reference point and two ancillary reference points. The two ancillary reference points are the anterior commissure and the posterior commissure. And the principal reference point is the midpoint of two ancillary reference points. It resides in the center of whole brain. From the principal reference point, Cartesian coordinate of x, y, z could be made to be the standard axial, sagittal, and coronal planes. PMID:20052359

  17. Legislation, standards and methods for mercury emissions control

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-04-15

    Mercury is an element of growing global concern. The United Nations Environment Programme plans to finalise and ratify a new global legally-binding convention on mercury by 2013. Canada already has legislation on mercury emissions from coal-fired utilities and the USA has recently released the new Mercury and Air Toxics Standard. Although other countries may not have mercury-specific legislation as such, many have legislation which results in significant co-benefit mercury reduction due to the installation of effective flue-gas cleaning technologies. This report reviews the current situation and trends in mercury emission legislation and, where possible, discusses the actions that will be taken under proposed or impending standards globally and regionally. The report also reviews the methods currently applied for mercury control and for mercury emission measurement with emphasis on the methodologies most appropriate for compliance. Examples of the methods of mercury control currently deployed in the USA, Canada and elsewhere are included.

  18. Standard test method for liquid impingement erosion using rotating apparatus

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This test method covers tests in which solid specimens are eroded or otherwise damaged by repeated discrete impacts of liquid drops or jets. Among the collateral forms of damage considered are degradation of optical properties of window materials, and penetration, separation, or destruction of coatings. The objective of the tests may be to determine the resistance to erosion or other damage of the materials or coatings under test, or to investigate the damage mechanisms and the effect of test variables. Because of the specialized nature of these tests and the desire in many cases to simulate to some degree the expected service environment, the specification of a standard apparatus is not deemed practicable. This test method gives guidance in setting up a test, and specifies test and analysis procedures and reporting requirements that can be followed even with quite widely differing materials, test facilities, and test conditions. It also provides a standardized scale of erosion resistance numbers applicab...

  19. Mercury Trapped Ion Frequency Standard for Ultra-Stable Reference Applications

    Science.gov (United States)

    Burt, Eric A. (Inventor); Hamell, Robert L. (Inventor); Tucker, Blake C. (Inventor); Larsen, Kameron (Inventor); Tjoelker, Robert L. (Inventor)

    2017-01-01

    An atomic clock including an ion trap assembly, a C-field coil positioned for generating a first magnetic field in the interrogation region of the ion trap assembly, a compensation coil positioned for generating a second magnetic field in the interrogation region, wherein the combination of the first and second magnetic fields produces an ion number-dependent second order Zeeman shift (Zeeman shift) in the resonance frequency that is opposite in sign to an ion number-dependent second order Doppler shift (Doppler shift) in the resonance frequency, the C-field coil has a radius selected using data indicating how changes in the radius affect an ion-number-dependent shift in the resonance frequency, such that a difference in magnitude between the Doppler shift and the Zeeman shift is controlled or reduced, and the resonance frequency, including the adjustment by the Zeeman shift, is used to obtain the frequency standard.

  20. Effective thermal conductivity of glass-fiber board and blanket standard reference materials

    International Nuclear Information System (INIS)

    Smith, D.R.; Hust, J.G.

    1983-01-01

    This chapter reports on measurements of effective thermal conductivity performed on a series of specimens of glass-fiber board and glass-fiber blanket. Explains that measurements of thermal conductivity were conducted as a function of temperature from 85 to 360 K, of temperature difference with T=10 to 100 K, of bulk density from 11 to 148 kg/m 3 and for nitrogen, argon, and helium inter-fiber fill gases at pressures from atmospheric to high vacuum. Analyzes and compares results with values from the published literature and National Bureau of Standards (NBS) certification data for similar material. Gives polynomial expressions for the functional relation between conductivity, temperature, and density for board and for blanket

  1. Gas measuring apparatus with standardization means, and method therefor

    International Nuclear Information System (INIS)

    Typpo, P.M.

    1980-01-01

    An apparatus and a method for standardizing a gas measuring device has a source capable of emitting a beam of radiation aligned to impinge a detector. A housing means encloses the beam. The housing means has a plurality of apertures permitting the gas to enter the housing means, to intercept the beam, and to exit from the housing means. The device further comprises means for closing the apertures and a means for purging said gas from the housing means

  2. High sensitivity neutron activation analysis of environmental and biological standard reference materials

    International Nuclear Information System (INIS)

    Greenberg, R.R.; Fleming, R.F.; Zeisler, R.

    1984-01-01

    Neutron activation analysis is a sensitive method with unique capabilities for the analysis of environmental and biological samples. Since it is based upon the nuclear properties of the elements, it does not suffer from many of the chemical effects that plague other methods of analysis. Analyses can be performed either with no chemical treatment of the sample (instrumentally), or with separations of the elements of interest after neutron irradiation (radiochemically). Typical examples of both types of analysis are discussed, and data obtained for a number of environmental and biological SRMs are presented. (author)

  3. Isotachophoresis as a candidate reference method in analytical chemistry. Determination of sodium in serum

    NARCIS (Netherlands)

    Lemmens, A.A.G.; Reijenga, J.C.; Everaerts, F.M.; Janssen, R.T.P.; Hulsman, J.A.R.J.; Meijers, C.A.M.

    1985-01-01

    Isotachophoresis seems a likely candidate for a reference method, as it is more accurate and precise than common routine methods. The response is highly linear and depends on a well defined transport number of the leading ion, stability of the driving current, mobility of the separand, which is well

  4. An independent accurate reference method for the determination of chromium in biological materials

    NARCIS (Netherlands)

    Lagerwaard, A.; Woittiez, J.R.W.; de Goeij, J.J.M.

    1994-01-01

    A method for the determination of Cr in biological materials with high accuracy is reported for use as an independent reference method. It is based on radiochemical neutron activation analysis (RNAA) in combination with an individual yield determination based on the online yield principle. A

  5. Comparison of Standard and Fast Charging Methods for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Petr Chlebis

    2014-01-01

    Full Text Available This paper describes a comparison of standard and fast charging methods used in the field of electric vehicles and also comparison of their efficiency in terms of electrical energy consumption. The comparison was performed on three-phase buck converter, which was designed for EV’s fast charging station. The results were obtained by both mathematical and simulation methods. The laboratory model of entire physical application, which will be further used for simulation results verification, is being built in these days.

  6. [Personalizing the reference level: gold standard to evaluate the quality of service perceived].

    Science.gov (United States)

    Rodrigo-Rincón, I; Reyes-Pérez, M; Martínez-Lozano, M E

    2014-01-01

    To know the cutoff point at which in-house Nuclear Medicine Department (MND) customers consider that the quality of service is good (personalized cutoff). We conducted a survey of the professionals who had requested at least 5 tests to the Nuclear Medicine Department. A total of 71 doctors responded (response rate: 30%). A question was added to the questionnaire for the user to establish a cutoff point for which they would consider the quality of service as good. The quality non-conformities, areas of improvement and strong points of the six questions measuring the quality of service (Likert scale 0 to 10) were compared with two different thresholds: personalized cutoff and one proposed by the service itself a priori. Test statistics: binomial and Student's t-test for paired data. A cutoff value of 7 was proposed by the service as a reference while 68.1% of respondents suggested a cutoff above 7 points (mean 7.9 points). The 6 elements of perceived quality were considered strong points with the cutoff proposed by the MND, while there were 3 detected with the personalized threshold. Thirteen percent of the answers were nonconformities with the service cutoff versus 19.2% with the personalized one, the differences being statistically significant (difference 95% CI 6.44%:0,83-12.06). The final image of the perceived quality of an in-house customer is different when using the cutoff established by the Department versus the personalized cutoff given by the respondent. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

  7. Reference methods and materials. A programme of support for regional and global marine pollution assessments

    International Nuclear Information System (INIS)

    1990-01-01

    This document describes a programme of comprehensive support for regional and global marine pollution assessments developed by the United Nations Environment Programme (UNEP) in cooperation with the International Atomic Energy Agency (IAEA) and the Intergovernmental Oceanographic Commission (IOC) and with the collaboration of a number of other United Nations Specialized agencies including the Food and Agriculture Organisation (FAO), the World Meteorological Organisation (WMO), the World Health Organisation (WHO) and the International Maritime Organisation (IMO). Two of the principle components of this programme, Reference Methods and Reference materials are given special attention in this document and a full Reference Method catalogue is included, giving details of over 80 methods currently available or in an advanced stage of preparation and testing. It is important that these methods are seen as a functional component of a much wider strategy necessary for assuring good quality and intercomparable data for regional and global pollution monitoring and the user is encouraged to read this document carefully before employing Reference Methods and Reference Materials in his/her laboratory. 3 figs

  8. Photon and proton activation analysis of iron and steel standards using the internal standard method coupled with the standard addition method

    International Nuclear Information System (INIS)

    Masumoto, K.; Hara, M.; Hasegawa, D.; Iino, E.; Yagi, M.

    1997-01-01

    The internal standard method coupled with the standard addition method has been applied to photon activation analysis and proton activation analysis of minor elements and trace impurities in various types of iron and steel samples issued by the Iron and Steel Institute of Japan (ISIJ). Samples and standard addition samples were once dissolved to mix homogeneously, an internal standard and elements to be determined and solidified as a silica-gel to make a similar matrix composition and geometry. Cerium and yttrium were used as an internal standard in photon and proton activation, respectively. In photon activation, 20 MeV electron beam was used for bremsstrahlung irradiation to reduce matrix activity and nuclear interference reactions, and the results were compared with those of 30 MeV irradiation. In proton activation, iron was removed by the MIBK extraction method after dissolving samples to reduce the radioactivity of 56 Co from iron via 56 Fe(p, n) 56 Co reaction. The results of proton and photon activation analysis were in good agreement with the standard values of ISIJ. (author)

  9. The standardisation of trace elements in international biological standard reference materials with neutron activation analysis and atomic absorption spectrophotometry

    International Nuclear Information System (INIS)

    Pieterse, H.

    1981-12-01

    An investigation was undertaken into the analytical procedures and the identification of problem areas, for the certification of a new biological standard reference material supplied by the International Atomic Energy Agency, namely, a human hair sample designated as HH-I. The analyses comprised the determination of the elements As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Sb, Se, and Zn in the hair sample by using two analytical techniques, namely, Instrumental Neutron Activation Analysis and Atomic Absorption. Three other certified biological reference materials, namely, Orchard Leaves (ORCH-L), Sea Plant Material (SPM-I) and Copepod (MAA-I) were used as control standards. Determinations were made of the moisture content of the samples, using varying conditions of drying, and the necessary corrections were applied to all analytical results so that the final elemental values related to dry weight of samples. Attention was also given to the possible loss of specific elements during ashing of the samples prior to the actual instrumental analysis. The results obtained for the hair sample by the two techniques were in good agreement for the elements Co, Fe, Mn, and Zn, but did not agree for the elements Cr and Sb. As, Hg and Se could only be determined with Instrumental Neutron Activation Analysis, and Cd, Cu and Ni only with Atomic Absorption. Most of the results obtained for the three control standard reference materials were within the ranges specified for the individual elements in each sample. The analytical procedures used for determining Cd, Cr, Cu, Ni and Sb with Instrumental Neutron Activation Analysis and As, Cr, Sb and Se with Atomic Absorption, need further investigation. The measurement of the moisture content and the ashing of samples also require further investigation with a view to improving accuracy

  10. 77 FR 55832 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method

    Science.gov (United States)

    2012-09-11

    ... automated monitoring method utilizing a measurement principle based on sample collection by filtration and... 58. Questions concerning the commercial availability or technical aspects of the method should be...

  11. Calibration of atomic force microscope cantilevers using standard and inverted static methods assisted by FIB-milled spatial markers

    International Nuclear Information System (INIS)

    Slattery, Ashley D; Blanch, Adam J; Quinton, Jamie S; Gibson, Christopher T

    2013-01-01

    Static methods to determine the spring constant of AFM cantilevers have been widely used in the scientific community since the importance of such calibration techniques was established nearly 20 years ago. The most commonly used static techniques involve loading a trial cantilever with a known force by pressing it against a pre-calibrated standard or reference cantilever. These reference cantilever methods have a number of sources of uncertainty, which include the uncertainty in the measured spring constant of the standard cantilever, the exact position of the loading point on the reference cantilever and how closely the spring constant of the trial and reference cantilever match. We present a technique that enables users to minimize these uncertainties by creating spatial markers on reference cantilevers using a focused ion beam (FIB). We demonstrate that by combining FIB spatial markers with an inverted reference cantilever method, AFM cantilevers can be accurately calibrated without the tip of the test cantilever contacting a surface. This work also demonstrates that for V-shaped cantilevers it is possible to determine the precise loading position by AFM imaging the section of the cantilever where the two arms join. Removing tip-to-surface contact in both the reference cantilever method and sensitivity calibration is a significant improvement, since this is an important consideration for AFM users that require the imaging tip to remain in pristine condition before commencing measurements. Uncertainties of between 5 and 10% are routinely achievable with these methods. (paper)

  12. Comparison of a New Cobinamide-Based Method to a Standard Laboratory Method for Measuring Cyanide in Human Blood

    Science.gov (United States)

    Swezey, Robert; Shinn, Walter; Green, Carol; Drover, David R.; Hammer, Gregory B.; Schulman, Scott R.; Zajicek, Anne; Jett, David A.; Boss, Gerry R.

    2013-01-01

    Most hospital laboratories do not measure blood cyanide concentrations, and samples must be sent to reference laboratories. A simple method is needed for measuring cyanide in hospitals. The authors previously developed a method to quantify cyanide based on the high binding affinity of the vitamin B12 analog, cobinamide, for cyanide and a major spectral change observed for cyanide-bound cobinamide. This method is now validated in human blood, and the findings include a mean inter-assay accuracy of 99.1%, precision of 8.75% and a lower limit of quantification of 3.27 µM cyanide. The method was applied to blood samples from children treated with sodium nitroprusside and it yielded measurable results in 88 of 172 samples (51%), whereas the reference laboratory yielded results in only 19 samples (11%). In all 19 samples, the cobinamide-based method also yielded measurable results. The two methods showed reasonable agreement when analyzed by linear regression, but not when analyzed by a standard error of the estimate or paired t-test. Differences in results between the two methods may be because samples were assayed at different times on different sample types. The cobinamide-based method is applicable to human blood, and can be used in hospital laboratories and emergency rooms. PMID:23653045

  13. Validation of a motor activity system by a robotically controlled vehicle and using standard reference compounds.

    Science.gov (United States)

    Patterson, John P; Markgraf, Carrie G; Cirino, Maria; Bass, Alan S

    2005-01-01

    A series of experiments were undertaken to evaluate the accuracy, precision, specificity, and sensitivity of an automated, infrared photo beam-based open field motor activity system, the MotorMonitor v. 4.01, Hamilton-Kinder, LLC, for use in a good laboratory practices (GLP) Safety Pharmacology laboratory. This evaluation consisted of two phases: (1) system validation, employing known inputs using the EM-100 Controller Photo Beam Validation System, a robotically controlled vehicle representing a rodent and (2) biologic validation, employing groups of rats treated with the standard pharmacologic agents diazepam or D-amphetamine. The MotorMonitor's parameters that described the open-field activity of a subject were: basic movements, total distance, fine movements, x/y horizontal ambulations, rearing, and total rest time. These measurements were evaluated over a number of zones within each enclosure. System validation with the EM-100 Controller Photo Beam Validation System showed that all the parameters accurately and precisely measured what they were intended to measure, with the exception of fine movements and x/y ambulations. Biologic validation using the central nervous system depressant diazepam at 1, 2, or 5 mg/kg, i.p. produced the expected dose-dependent reduction in rat motor activity. In contrast, the central nervous system stimulant D-amphetamine produced the expected increases in rat motor activity at 0.1 and 1 mg/kg, i.p, demonstrating the specificity and sensitivity of the system. Taken together, these studies of the accuracy, precision, specificity, and sensitivity show the importance of both system and biologic validation in the evaluation of an automated open field motor activity system for use in a GLP compliant laboratory.

  14. Reference and standard benchmark field consensus fission yields for U.S. reactor dosimetry programs

    International Nuclear Information System (INIS)

    Gilliam, D.M.; Helmer, R.G.; Greenwood, R.C.; Rogers, J.W.; Heinrich, R.R.; Popek, R.J.; Kellogg, L.S.; Lippincott, E.P.; Hansen, G.E.; Zimmer, W.H.

    1977-01-01

    Measured fission product yields are reported for three benchmark neutron fields--the BIG-10 fast critical assembly at Los Alamos, the CFRMF fast neutron cavity at INEL, and the thermal column of the NBS Research Reactor. These measurements were carried out by participants in the Interlaboratory LMFBR Reaction Rates (ILRR) program. Fission product generation rates were determined by post-irradiation analysis of gamma-ray emission from fission activation foils. The gamma counting was performed by Ge(Li) spectrometry at INEL, ANL, and HEDL; the sample sent to INEL was also analyzed by NaI(Tl) spectrometry for Ba-140 content. The fission rates were determined by means of the NBS Double Fission Ionization Chamber using thin deposits of each of the fissionable isotopes. Four fissionable isotopes were included in the fast neutron field measurements; these were U-235, U-238, Pu-239, and Np-237. Only U-235 was included in the thermal neutron yield measurements. For the fast neutron fields, consensus yields were determined for three fission product isotopes--Zr-95, Ru-103, and Ba-140. For these fission product isotopes, a separately activated foil was analyzed by each of the three gamma counting laboratories. The experimental standard deviation of the three independent results was typically +- 1.5%. For the thermal neutron field, a consensus value for the Cs-137 yield was also obtained. Subsidiary fission yields are also reported for other isotopes which were studied less intensively (usually by only one of the participating laboratories). Comparisons with EBR-II fast reactor yields from destructive analysis and with ENDF/B recommended values are given

  15. Standard Reference Line Combined with One-Point Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) to Quantitatively Analyze Stainless and Heat Resistant Steel.

    Science.gov (United States)

    Fu, Hongbo; Wang, Huadong; Jia, Junwei; Ni, Zhibo; Dong, Fengzhong

    2018-01-01

    Due to the influence of major elements' self-absorption, scarce observable spectral lines of trace elements, and relative efficiency correction of experimental system, accurate quantitative analysis with calibration-free laser-induced breakdown spectroscopy (CF-LIBS) is in fact not easy. In order to overcome these difficulties, standard reference line (SRL) combined with one-point calibration (OPC) is used to analyze six elements in three stainless-steel and five heat-resistant steel samples. The Stark broadening and Saha - Boltzmann plot of Fe are used to calculate the electron density and the plasma temperature, respectively. In the present work, we tested the original SRL method, the SRL with the OPC method, and intercept with the OPC method. The final calculation results show that the latter two methods can effectively improve the overall accuracy of quantitative analysis and the detection limits of trace elements.

  16. Standard Test Method for Normal Spectral Emittance at Elevated Temperatures

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1972-01-01

    1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm. 1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute. 1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this stan...

  17. 77 FR 32632 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Science.gov (United States)

    2012-06-01

    ... Methods: Designation of Three New Equivalent Methods AGENCY: Environmental Protection Agency. ACTION... accordance with 40 CFR Part 53, three new equivalent methods: One for measuring concentrations of nitrogen... INFORMATION: In accordance with regulations at 40 CFR Part 53, the EPA evaluates various methods for...

  18. 78 FR 67360 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Five New Equivalent Methods

    Science.gov (United States)

    2013-11-12

    ... Methods: Designation of Five New Equivalent Methods AGENCY: Office of Research and Development; Environmental Protection Agency (EPA). ACTION: Notice of the designation of five new equivalent methods for...) has designated, in accordance with 40 CFR Part 53, five new equivalent methods, one for measuring...

  19. 77 FR 60985 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Science.gov (United States)

    2012-10-05

    ... Methods: Designation of Three New Equivalent Methods AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of three new equivalent methods for monitoring ambient air quality. SUMMARY... equivalent methods, one for measuring concentrations of PM 2.5 , one for measuring concentrations of PM 10...

  20. A novel strategy with standardized reference extract qualification and single compound quantitative evaluation for quality control of Panax notoginseng used as a functional food.

    Science.gov (United States)

    Li, S P; Qiao, C F; Chen, Y W; Zhao, J; Cui, X M; Zhang, Q W; Liu, X M; Hu, D J

    2013-10-25

    Root of Panax notoginseng (Burk.) F.H. Chen (Sanqi in Chinese) is one of traditional Chinese medicines (TCMs) based functional food. Saponins are the major bioactive components. The shortage of reference compounds or chemical standards is one of the main bottlenecks for quality control of TCMs. A novel strategy, i.e. standardized reference extract based qualification and single calibrated components directly quantitative estimation of multiple analytes, was proposed to easily and effectively control the quality of natural functional foods such as Sanqi. The feasibility and credibility of this methodology were also assessed with a developed fast HPLC method. Five saponins, including ginsenoside Rg1, Re, Rb1, Rd and notoginsenoside R1 were rapidly separated using a conventional HPLC in 20 min. The quantification method was also compared with individual calibration curve method. The strategy is feasible and credible, which is easily and effectively adapted for improving the quality control of natural functional foods such as Sanqi. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Standardization method for alpha and beta surface sources

    Energy Technology Data Exchange (ETDEWEB)

    Sahagia, M; Grigorescu, E L; Razdolescu, A C; Ivan, C [Institute of Physics and Nuclear Engineering, Institute of Atomic Physics, PO Box MG-6, R-76900 Bucharest, (Romania)

    1994-01-01

    The installation and method of standardization of large surface alpha and beta sources are presented. A multiwire, flow-type proportional counter and the associated electronics is used. The counter is placed in a lead-shield. The response of the system in (s[sup -1]/Bq) or (s[sup -1]/(particle x s[sup -1])) was determined for [sup 241] Am, [sup 239] Pu, [sup 147] Pm, [sup 204] Tl, [sup 90](Sr+Y) and [sup 137] Cs using standard sources with different dimensions, from some mm[sup 2] to 180 x 220 mm[sup 2]. The system was legally attested for expanded uncertainties of +7%. (Author).

  2. Model Reference Adaptive Control of the Air Flow Rate of Centrifugal Compressor Using State Space Method

    International Nuclear Information System (INIS)

    Han, Jaeyoung; Jung, Mooncheong; Yu, Sangseok; Yi, Sun

    2016-01-01

    In this study, a model reference adaptive controller is developed to regulate the outlet air flow rate of centrifugal compressor for automotive supercharger. The centrifugal compressor is developed using the analytical based method to predict the transient behavior of operating and the designed model is validated with experimental data to confirm the system accuracy. The model reference adaptive control structure consists of a compressor model and a MRAC(model reference adaptive control) mechanism. The feedback control do not robust with variation of system parameter but the applied adaptive control is robust even if the system parameter is changed. As a result, the MRAC was regulated to reference air flow rate. Also MRAC was found to be more robust control compared with the feedback control even if the system parameter is changed.

  3. Model Reference Adaptive Control of the Air Flow Rate of Centrifugal Compressor Using State Space Method

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jaeyoung; Jung, Mooncheong; Yu, Sangseok [Chungnam Nat’l Univ., Daejeon (Korea, Republic of); Yi, Sun [North Carolina A and T State Univ., Raleigh (United States)

    2016-08-15

    In this study, a model reference adaptive controller is developed to regulate the outlet air flow rate of centrifugal compressor for automotive supercharger. The centrifugal compressor is developed using the analytical based method to predict the transient behavior of operating and the designed model is validated with experimental data to confirm the system accuracy. The model reference adaptive control structure consists of a compressor model and a MRAC(model reference adaptive control) mechanism. The feedback control do not robust with variation of system parameter but the applied adaptive control is robust even if the system parameter is changed. As a result, the MRAC was regulated to reference air flow rate. Also MRAC was found to be more robust control compared with the feedback control even if the system parameter is changed.

  4. Assessment of the reference stress method for combined tensile bending and thermal loading

    International Nuclear Information System (INIS)

    Philipp, A.; Munz, D.

    1984-01-01

    The reference stress method has been investigated for combined tensile, bending and thermal loading by considering a uniformly bent beam subjected to superimposed tensile stress and lateral temperature gradients. The creep deformation of the beam can be calculated numerically applying a Norton-type creep law. It turns out that the ratio of curvature rate to strain at the outer fiber depends on the creep exponent. Therefore, the reference stresses for these two quantities must be expected to be different in general. In most load cases, however, it is possible to determine a reference stress which can be used to describe the complete deformation of the beam. The only exception is the case of high tensile loading if the side exposed to higher tensile stress is cooler. Approximate solutions for the reference stress which rely on elastic and limit analyses, can be used only for estimates because they lead to extremely non-conservative predictions. (author)

  5. Standard CMMIsm Appraisal Method for Process Improvement (SCAMPIsm), Version 1.1: Method Definition Document

    National Research Council Canada - National Science Library

    2001-01-01

    The Standard CMMI Appraisal Method for Process Improvement (SCAMPI(Service Mark)) is designed to provide benchmark quality ratings relative to Capability Maturity Model(registered) Integration (CMMI(Service Mark)) models...

  6. Cutibacterium acnes molecular typing: time to standardize the method.

    Science.gov (United States)

    Dagnelie, M-A; Khammari, A; Dréno, B; Corvec, S

    2018-03-12

    The Gram-positive, anaerobic/aerotolerant bacterium Cutibacterium acnes is a commensal of healthy human skin; it is subdivided into six main phylogenetic groups or phylotypes: IA1, IA2, IB, IC, II and III. To decipher how far specific subgroups of C. acnes are involved in disease physiopathology, different molecular typing methods have been developed to identify these subgroups: i.e. phylotypes, clonal complexes, and types defined by single-locus sequence typing (SLST). However, as several molecular typing methods have been developed over the last decade, it has become a difficult task to compare the results from one article to another. Based on the scientific literature, the aim of this narrative review is to propose a standardized method to perform molecular typing of C. acnes, according to the degree of resolution needed (phylotypes, clonal complexes, or SLST types). We discuss the existing different typing methods from a critical point of view, emphasizing their advantages and drawbacks, and we identify the most frequently used methods. We propose a consensus algorithm according to the needed phylogeny resolution level. We first propose to use multiplex PCR for phylotype identification, MLST9 for clonal complex determination, and SLST for phylogeny investigation including numerous isolates. There is an obvious need to create a consensus about molecular typing methods for C. acnes. This standardization will facilitate the comparison of results between one article and another, and also the interpretation of clinical data. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  7. A standardized method for beam design in neutron capture therapy

    International Nuclear Information System (INIS)

    Storr, G.J.: Harrington, B.V.

    1993-01-01

    A desirable end point for a given beam design for Neutron Capture Therapy (NCT) should be quantitative description of tumour control probability and normal tissue damage. Achieving this goal will ultimately rely on data from NCT human clinical trials. Traditional descriptions of beam designs have used a variety of assessment methods to quantify proposed or installed beam designs. These methods include measurement and calculation of open-quotes free fieldclose quotes parameters, such as neutron and gamma flux intensities and energy spectra, and figures-of-merit in tissue equivalent phantoms. The authors propose here a standardized method for beam design in NCT. This method would allow all proposed and existing NCT beam facilities to be compared equally. The traditional approach to determining a quantitative description of tumour control probability and normal tissue damage in NCT research may be described by the following path: Beam design → dosimetry → macroscopic effects → microscopic effects. Methods exist that allow neutron and gamma fluxes and energy dependence to be calculated and measured to good accuracy. By using this information and intermediate dosimetric quantities such as kerma factors for neutrons and gammas, macroscopic effect (absorbed dose) in geometries of tissue or tissue-equivalent materials can be calculated. After this stage, for NCT the data begins to become more sparse and in some areas ambiguous. Uncertainties in the Relative Biological Effectiveness (RBE) of some NCT dose components means that beam designs based on assumptions considered valid a few years ago may have to be reassessed. A standard method is therefore useful for comparing different NCT facilities

  8. Consequences of new reference climate years according to the Dutch standard NEN 5060; Gevolgen nieuwe referentieklimaatjaren volgens NEN 5060

    Energy Technology Data Exchange (ETDEWEB)

    Hooft, E.N. ' t [Grontmij, Amersfoort (Netherlands)

    2009-02-15

    Because of the climate changes the reference year 1964-1965 is a topic of discussion as on appropriate climate file for the design of climate installations. Therefor, in the Netherlands, new climate reference years are developed for temperature and energy calculations, outlined in the Dutch standard NEN 5060 (Hygrothermal properties of buildings. Reference climate data). This article shows for a nursing home the consequences on the design, energy consumption and energy costs of the climate installation. [Dutch] Vanwege de klimaatveranderingen, die een duidelijke trend naar warmere jaren laat zien, staat het referentiejaar 1964-1965 ter discussie als geschikt klimaatbestand voor bet ontwerp van klimaatinstallaties. Om die reden zijn voor Nederland nieuwe referentieklimaatjaren ontwikkeld voor temperatuur- en energieberekeningen, die zijn opgenomen in NEN 5060 (Hygro-thermische eigenschappen van gebouwen. Referentieklimaatgegevens), die als definitieve versie is verschenen. Dit artikel laat aan de hand van een rekenstudie aan een referentiegebouw in de gezondheidszorg (verpleeghuis) zien wat de consequenties zijn van de nieuw ontwikkelde referentieklimaatjaren op bet ontwerp, het energiegebruik en de energiekosten van de klimaatinstallatie.

  9. Standardized Method for High-throughput Sterilization of Arabidopsis Seeds.

    Science.gov (United States)

    Lindsey, Benson E; Rivero, Luz; Calhoun, Chistopher S; Grotewold, Erich; Brkljacic, Jelena

    2017-10-17

    Arabidopsis thaliana (Arabidopsis) seedlings often need to be grown on sterile media. This requires prior seed sterilization to prevent the growth of microbial contaminants present on the seed surface. Currently, Arabidopsis seeds are sterilized using two distinct sterilization techniques in conditions that differ slightly between labs and have not been standardized, often resulting in only partially effective sterilization or in excessive seed mortality. Most of these methods are also not easily scalable to a large number of seed lines of diverse genotypes. As technologies for high-throughput analysis of Arabidopsis continue to proliferate, standardized techniques for sterilizing large numbers of seeds of different genotypes are becoming essential for conducting these types of experiments. The response of a number of Arabidopsis lines to two different sterilization techniques was evaluated based on seed germination rate and the level of seed contamination with microbes and other pathogens. The treatments included different concentrations of sterilizing agents and times of exposure, combined to determine optimal conditions for Arabidopsis seed sterilization. Optimized protocols have been developed for two different sterilization methods: bleach (liquid-phase) and chlorine (Cl2) gas (vapor-phase), both resulting in high seed germination rates and minimal microbial contamination. The utility of these protocols was illustrated through the testing of both wild type and mutant seeds with a range of germination potentials. Our results show that seeds can be effectively sterilized using either method without excessive seed mortality, although detrimental effects of sterilization were observed for seeds with lower than optimal germination potential. In addition, an equation was developed to enable researchers to apply the standardized chlorine gas sterilization conditions to airtight containers of different sizes. The protocols described here allow easy, efficient, and

  10. Deformation of two-phase aggregates using standard numerical methods

    Science.gov (United States)

    Duretz, Thibault; Yamato, Philippe; Schmalholz, Stefan M.

    2013-04-01

    Geodynamic problems often involve the large deformation of material encompassing material boundaries. In geophysical fluids, such boundaries often coincide with a discontinuity in the viscosity (or effective viscosity) field and subsequently in the pressure field. Here, we employ popular implementations of the finite difference and finite element methods for solving viscous flow problems. On one hand, we implemented finite difference method coupled with a Lagrangian marker-in-cell technique to represent the deforming fluid. Thanks to it Eulerian nature, this method has a limited geometric flexibility but is characterized by a light and stable discretization. On the other hand, we employ the Lagrangian finite element method which offers full geometric flexibility at the cost of relatively heavier discretization. In order to test the accuracy of the finite difference scheme, we ran large strain simple shear deformation of aggregates containing either weak of strong circular inclusion (1e6 viscosity ratio). The results, obtained for different grid resolutions, are compared to Lagrangian finite element results which are considered as reference solution. The comparison is then used to establish up to which strain can finite difference simulations be run given the nature of the inclusions (dimensions, viscosity) and the resolution of the Eulerian mesh.

  11. Development of a certified reference material for composition of high-purity copper as a transfer standard within GET 176-2013

    Directory of Open Access Journals (Sweden)

    Veniamin M. Zyskin

    2017-01-01

    Full Text Available Introduction. The paper gives information on the development of a certified reference material (CRM for composition of high-purity copper (Cu CRM UNIIM. The CRM is included as the transfer standard into the State primary standard of the mass (molar fraction and mass (molar concentration of the component in liquid and solid substances and materials based on coulometry GET 176-2013.Materials and methods. The CRM represents pieces of oxygen-free copper wire rod, brand KMB, produced according to GOST R 53803-2010, weighing from 0.5 to 1g. The CRM is packed in plastic vials with the capacity of 30 or 50 cm3. The certified characteristic of the CRM is copper mass fraction in copper wire rod, expressed in percentages. The certified value for copper mass fraction was established by the primary method of controlled-potential coulometry using the State primary standard GET 176-2013.Results. The permitted interval of the certified value for copper mass fraction in the CRM is from 99,950 % to 100,000 %. The relative expanded uncertainty (k=2 of the certified value for copper mass fraction does not exceed 0,030 %; the relative standard uncertainty due to inhomogeneity does not exceed 0.010 %; the relative standard uncertainty due to instability does not exceed 0.010 %. The shelf life of the developed CRM is 10 years provided that standard storage conditions are ensured.Discussion and conclusions. The developed CRM is included into the State register of type approved RMs under the number GSO 10800-2016. The CRM of high-purity copper (Cu CRM UNIIM as a transfer standard is intended for reproduction, storage and transfer of the copper mass fraction unit to other reference materials and chemical reagents by the method of comparison using a comparator and by conducting direct measurements. This CRM may also be used:– for verification of measuring instruments (MIs according to the state verification schedule described in GOST R 8.735.0-2014,– for calibration

  12. A standard curve based method for relative real time PCR data processing

    Directory of Open Access Journals (Sweden)

    Krause Andreas

    2005-03-01

    Full Text Available Abstract Background Currently real time PCR is the most precise method by which to measure gene expression. The method generates a large amount of raw numerical data and processing may notably influence final results. The data processing is based either on standard curves or on PCR efficiency assessment. At the moment, the PCR efficiency approach is preferred in relative PCR whilst the standard curve is often used for absolute PCR. However, there are no barriers to employ standard curves for relative PCR. This article provides an implementation of the standard curve method and discusses its advantages and limitations in relative real time PCR. Results We designed a procedure for data processing in relative real time PCR. The procedure completely avoids PCR efficiency assessment, minimizes operator involvement and provides a statistical assessment of intra-assay variation. The procedure includes the following steps. (I Noise is filtered from raw fluorescence readings by smoothing, baseline subtraction and amplitude normalization. (II The optimal threshold is selected automatically from regression parameters of the standard curve. (III Crossing points (CPs are derived directly from coordinates of points where the threshold line crosses fluorescence plots obtained after the noise filtering. (IV The means and their variances are calculated for CPs in PCR replicas. (V The final results are derived from the CPs' means. The CPs' variances are traced to results by the law of error propagation. A detailed description and analysis of this data processing is provided. The limitations associated with the use of parametric statistical methods and amplitude normalization are specifically analyzed and found fit to the routine laboratory practice. Different options are discussed for aggregation of data obtained from multiple reference genes. Conclusion A standard curve based procedure for PCR data processing has been compiled and validated. It illustrates that

  13. Wavelength selection method with standard deviation: application to pulse oximetry.

    Science.gov (United States)

    Vazquez-Jaccaud, Camille; Paez, Gonzalo; Strojnik, Marija

    2011-07-01

    Near-infrared spectroscopy provides useful biological information after the radiation has penetrated through the tissue, within the therapeutic window. One of the significant shortcomings of the current applications of spectroscopic techniques to a live subject is that the subject may be uncooperative and the sample undergoes significant temporal variations, due to his health status that, from radiometric point of view, introduce measurement noise. We describe a novel wavelength selection method for monitoring, based on a standard deviation map, that allows low-noise sensitivity. It may be used with spectral transillumination, transmission, or reflection signals, including those corrupted by noise and unavoidable temporal effects. We apply it to the selection of two wavelengths for the case of pulse oximetry. Using spectroscopic data, we generate a map of standard deviation that we propose as a figure-of-merit in the presence of the noise introduced by the living subject. Even in the presence of diverse sources of noise, we identify four wavelength domains with standard deviation, minimally sensitive to temporal noise, and two wavelengths domains with low sensitivity to temporal noise.

  14. Task-oriented comparison of power spectral density estimation methods for quantifying acoustic attenuation in diagnostic ultrasound using a reference phantom method.

    Science.gov (United States)

    Rosado-Mendez, Ivan M; Nam, Kibo; Hall, Timothy J; Zagzebski, James A

    2013-07-01

    Reported here is a phantom-based comparison of methods for determining the power spectral density (PSD) of ultrasound backscattered signals. Those power spectral density values are then used to estimate parameters describing α(f), the frequency dependence of the acoustic attenuation coefficient. Phantoms were scanned with a clinical system equipped with a research interface to obtain radiofrequency echo data. Attenuation, modeled as a power law α(f)= α0 f (β), was estimated using a reference phantom method. The power spectral density was estimated using the short-time Fourier transform (STFT), Welch's periodogram, and Thomson's multitaper technique, and performance was analyzed when limiting the size of the parameter-estimation region. Errors were quantified by the bias and standard deviation of the α0 and β estimates, and by the overall power-law fit error (FE). For parameter estimation regions larger than ~34 pulse lengths (~1 cm for this experiment), an overall power-law FE of 4% was achieved with all spectral estimation methods. With smaller parameter estimation regions as in parametric image formation, the bias and standard deviation of the α0 and β estimates depended on the size of the parameter estimation region. Here, the multitaper method reduced the standard deviation of the α0 and β estimates compared with those using the other techniques. The results provide guidance for choosing methods for estimating the power spectral density in quantitative ultrasound methods.

  15. Evaluation and Recalibration of Empirical Constant for Estimation of Reference Crop Evapotranspiration against the Modified Penman Method

    Science.gov (United States)

    Sasireka, K.; Jagan Mohan Reddy, C.; Charan Reddy, C.; Ramakrishnan, K.

    2017-07-01

    The major demand in our country is irrigation demand. Looking to the low irrigation potential and small water resources, it is felt necessary to see that water must be used economically and efficiently. This may be achieved by using latest methods of determination of water requirements for crops and applying the proper water management practices. Evapotranspiration (ET) is a basic for calculation of water requirement for crops. The various popular empirical equations for reference crop evapotranspiration (ETr) belong to three categories namely, Temperature, Radiation based methods and Combined methods. The above methods are site specific; hence it is necessary to recalibrate the coefficients for applying them in India. In the present paper, the standard combined method namely FAO modified Penman method was used to recalibrate the constants in temperature based (TB) methods and it can also be used to determine the ETr for the selected station. Four TB evapotranspiration models namely Blaney-Criddle, Romanenko, Kharrufa, and, Thronthwaite methods are recalibrated and the constant in each method are redefined for the data from Lekkur station, Cuddalore district in India. The result shows that, large error existed when ETr has been calculated with original constants. Hence regression equations were developed to minimise these variations in magnitude. It was found that out of four methods the Blaney-Criddle method suits better for the selected region.

  16. Standard Test Method for Measuring Binocular Disparity in Transparent Parts

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers the amount of binocular disparity that is induced by transparent parts such as aircraft windscreens, canopies, HUD combining glasses, visors, or goggles. This test method may be applied to parts of any size, shape, or thickness, individually or in combination, so as to determine the contribution of each transparent part to the overall binocular disparity present in the total “viewing system” being used by a human operator. 1.2 This test method represents one of several techniques that are available for measuring binocular disparity, but is the only technique that yields a quantitative figure of merit that can be related to operator visual performance. 1.3 This test method employs apparatus currently being used in the measurement of optical angular deviation under Method F 801. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not con...

  17. A new method of 3-D cephalometry Part I: the anatomic Cartesian 3-D reference system.

    NARCIS (Netherlands)

    Swennen, G.R.J.; Schutyser, F.A.C.; Barth, E.L.; Groeve, P. De; Mey, A. De

    2006-01-01

    The purpose of this study was to present a new innovative three-dimensional (3-D) cephalometric method. Part I deals with the set-up and validation of a voxel-based semi-automatic 3-D cephalometric reference system. The CT data (DICOM 3.0 files) of 20 control patients with normal skeletal

  18. Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) with Standard Reference Line for the Analysis of Stainless Steel.

    Science.gov (United States)

    Fu, Hongbo; Dong, Fengzhong; Wang, Huadong; Jia, Junwei; Ni, Zhibo

    2017-08-01

    In this work, calibration-free laser-induced breakdown spectroscopy (CF-LIBS) is used to analyze a certified stainless steel sample. Due to self-absorption of the spectral lines from the major element Fe and the sparse lines of trace elements, it is usually not easy to construct the Boltzmann plots of all species. A standard reference line method is proposed here to solve this difficulty under the assumption of local thermodynamic equilibrium so that the same temperature value for all elements present into the plasma can be considered. Based on the concentration and rich spectral lines of Fe, the Stark broadening of Fe(I) 381.584 nm and Saha-Boltzmann plots of this element are used to calculate the electron density and the plasma temperature, respectively. In order to determine the plasma temperature accurately, which is seriously affected by self-absorption, a pre-selection procedure for eliminating those spectral lines with strong self-absorption is employed. Then, one spectral line of each element is selected to calculate its corresponding concentration. The results from the standard reference lines with and without self-absorption of Fe are compared. This method allows us to measure trace element content and effectively avoid the adverse effects due to self-absorption.

  19. NEURO-SYSTEM OF AIMING AND STABILIZING WITH A REGULATOR ON THE BASIS OF STANDARD MODEL MODEL REFERENCE CONTROLLER

    Directory of Open Access Journals (Sweden)

    B.I. Kuznetsov

    2015-08-01

    Full Text Available The aim of this work is the synthesis of neural network aiming and stabilization system for the special equipment of moving objects with neuro-controller on the basis of standard model and performance comparison of the neural network system with the neural network predictive control. Build a block diagram of the neural network aiming and stabilization system, based on the subject control principle with PD-regulator in the position loop and with neuro-controller on the basis of standard model in the in the velocity loop. The neuro-controller on the basis of standard model Model Reference Controller is synthesized in the MATLAB Neural Network Toolbox and system simulation is performed. The studies show that the transient state variables of the system are oscillatory. Therefore, the neuro-controller with the prediction NN Predictive Controller should be used for aiming and stabilizing system to provide high dynamic characteristics achieved at the cost of higher complexity and computational cost.

  20. Determination of element concentrations in biological reference materials by solid sampling and other analytical methods

    International Nuclear Information System (INIS)

    Schauenburg, H.; Weigert, P.

    1992-01-01

    Using solid sampling with graphite furnace atomic absorption spectrometry (GFAAS), values for cadmium, copper, lead and zinc in six biological reference materials were obtained from up to four laboratories participating in three collaborative studies. These results are compared with those obtained with other methods used in routine analysis from laboratories of official food control. Under certain conditions solid sampling with GFAAS seems to be suitable for routine analysis as well as conventional methods. (orig.)

  1. Standard test methods for performance characteristics of metallic bonded resistance strain gages

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1992-01-01

    1.1 The purpose of this standard is to provide uniform test methods for the determination of strain gauge performance characteristics. Suggested testing equipment designs are included. 1.2 Test Methods E 251 describes methods and procedures for determining five strain gauge parameters: Section Part I—General Requirements 7 Part II—Resistance at a Reference Temperature 8 Part III—Gauge Factor at a Reference Temperature 9 Part IV—Temperature Coefficient of Gauge Factor\t10 Part V—Transverse Sensitivity\t11 Part VI—Thermal Output\t12 1.3 Strain gauges are very sensitive devices with essentially infinite resolution. Their response to strain, however, is low and great care must be exercised in their use. The performance characteristics identified by these test methods must be known to an acceptable accuracy to obtain meaningful results in field applications. 1.3.1 Strain gauge resistance is used to balance instrumentation circuits and to provide a reference value for measurements since all data are...

  2. SPM analysis of parametric (R)-[11C]PK11195 binding images: plasma input versus reference tissue parametric methods.

    Science.gov (United States)

    Schuitemaker, Alie; van Berckel, Bart N M; Kropholler, Marc A; Veltman, Dick J; Scheltens, Philip; Jonker, Cees; Lammertsma, Adriaan A; Boellaard, Ronald

    2007-05-01

    (R)-[11C]PK11195 has been used for quantifying cerebral microglial activation in vivo. In previous studies, both plasma input and reference tissue methods have been used, usually in combination with a region of interest (ROI) approach. Definition of ROIs, however, can be labourious and prone to interobserver variation. In addition, results are only obtained for predefined areas and (unexpected) signals in undefined areas may be missed. On the other hand, standard pharmacokinetic models are too sensitive to noise to calculate (R)-[11C]PK11195 binding on a voxel-by-voxel basis. Linearised versions of both plasma input and reference tissue models have been described, and these are more suitable for parametric imaging. The purpose of this study was to compare the performance of these plasma input and reference tissue parametric methods on the outcome of statistical parametric mapping (SPM) analysis of (R)-[11C]PK11195 binding. Dynamic (R)-[11C]PK11195 PET scans with arterial blood sampling were performed in 7 younger and 11 elderly healthy subjects. Parametric images of volume of distribution (Vd) and binding potential (BP) were generated using linearised versions of plasma input (Logan) and reference tissue (Reference Parametric Mapping) models. Images were compared at the group level using SPM with a two-sample t-test per voxel, both with and without proportional scaling. Parametric BP images without scaling provided the most sensitive framework for determining differences in (R)-[11C]PK11195 binding between younger and elderly subjects. Vd images could only demonstrate differences in (R)-[11C]PK11195 binding when analysed with proportional scaling due to intersubject variation in K1/k2 (blood-brain barrier transport and non-specific binding).

  3. Standard test method for measurement of roll wave optical distortion in heat-treated flat glass

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method is applicable to the determination of the peak-to-valley depth and peak-to-peak distances of the out-of-plane deformation referred to as roll wave which occurs in flat, heat-treated architectural glass substrates processed in a heat processing continuous or oscillating conveyance oven. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This test method does not address other flatness issues like edge kink, ream, pocket distortion, bow, or other distortions outside of roll wave as defined in this test method. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  4. Survey of total error of precipitation and homogeneous HDL-cholesterol methods and simultaneous evaluation of lyophilized saccharose-containing candidate reference materials for HDL-cholesterol

    NARCIS (Netherlands)

    C.M. Cobbaert (Christa); H. Baadenhuijsen; L. Zwang (Louwerens); C.W. Weykamp; P.N. Demacker; P.G.H. Mulder (Paul)

    1999-01-01

    textabstractBACKGROUND: Standardization of HDL-cholesterol is needed for risk assessment. We assessed for the first time the accuracy of HDL-cholesterol testing in The Netherlands and evaluated 11 candidate reference materials (CRMs). METHODS: The total error (TE) of

  5. Evaluation of the Reference Numerical Parameters of the Monthly Method in ISO 13790 Considering S/V Ratio

    Directory of Open Access Journals (Sweden)

    Hee-Jeong Kwak

    2015-01-01

    Full Text Available Many studies have investigated the accuracy of the numerical parameters in the application of the quasi steady-state calculation method. The aim of this study is to derive the reference numerical parameters of the ISO 13790 monthly method by reflecting the surface-to-volume (S/V ratio and the characteristics of the structures. The calculation process was established, and the parameters necessary to derive the reference numerical parameters were calculated based on the input data prepared for the established calculation processes. The reference numerical parameters were then derived through regression analyses of the calculated parameters and the time constant. The parameters obtained from an apartment building and the parameters of the international standard were both applied to the Passive House Planning Package (PHPP and EnergyPlus programs, and the results were analyzed in order to evaluate the validity of the results. The analysis revealed that the calculation results based on the parameters derived from this study yielded lower error rates than those based on the default parameters in ISO 13790. However, the differences were shown to be negligible in the case of high heat capacity.

  6. Benefits of a Pharmacology Antimalarial Reference Standard and Proficiency Testing Program Provided by the Worldwide Antimalarial Resistance Network (WWARN)

    Science.gov (United States)

    Lourens, Chris; Lindegardh, Niklas; Barnes, Karen I.; Guerin, Philippe J.; Sibley, Carol H.; White, Nicholas J.

    2014-01-01

    Comprehensive assessment of antimalarial drug resistance should include measurements of antimalarial blood or plasma concentrations in clinical trials and in individual assessments of treatment failure so that true resistance can be differentiated from inadequate drug exposure. Pharmacometric modeling is necessary to assess pharmacokinetic-pharmacodynamic relationships in different populations to optimize dosing. To accomplish both effectively and to allow comparison of data from different laboratories, it is essential that drug concentration measurement is accurate. Proficiency testing (PT) of laboratory procedures is necessary for verification of assay results. Within the Worldwide Antimalarial Resistance Network (WWARN), the goal of the quality assurance/quality control (QA/QC) program is to facilitate and sustain high-quality antimalarial assays. The QA/QC program consists of an international PT program for pharmacology laboratories and a reference material (RM) program for the provision of antimalarial drug standards, metabolites, and internal standards for laboratory use. The RM program currently distributes accurately weighed quantities of antimalarial drug standards, metabolites, and internal standards to 44 pharmacology, in vitro, and drug quality testing laboratories. The pharmacology PT program has sent samples to eight laboratories in four rounds of testing. WWARN technical experts have provided advice for correcting identified problems to improve performance of subsequent analysis and ultimately improved the quality of data. Many participants have demonstrated substantial improvements over subsequent rounds of PT. The WWARN QA/QC program has improved the quality and value of antimalarial drug measurement in laboratories globally. It is a model that has potential to be applied to strengthening laboratories more widely and improving the therapeutics of other infectious diseases. PMID:24777099

  7. Standardization of reagents and methods used in cytological and histological practice with emphasis on dyes, stains and chromogenic reagents

    DEFF Research Database (Denmark)

    Lyon, H O; De Leenheer, A P; Horobin, R W

    1994-01-01

    and stains through the preparation of reference materials and the development of chromatographic methods. An overview is presented of the problems concerned with standardization of the Romanowsky-Giemsa stain for cytological and histological application. Finally, the problem of how to convince routine dye...

  8. Recent advances in ratio primary reference measurement procedures (definitive methods) and their use in certification of reference materials and controlling assigned values in proficiency testing

    International Nuclear Information System (INIS)

    Dybczynski, R.S.; Polkowska-Motrenko, H.; Chajduk, E.; Danko, B.; Pyszynska, M.

    2014-01-01

    Three very accurate (definitive) methods by RNAA for the determination of Se, As and Fe respectively, which were recently elaborated in our laboratory, are reviewed and their use in certification of reference materials and in checking the assigned values in proficiency tests is demonstrated on several examples. According to VIM 3 nomenclature these methods may be called: ratio primary reference measurement procedures (RPRMPs). RPRMPs with their expanded uncertainties of 2.7-3.6 % are comparable to ID-MS methods and are the only methods of such high metrological quality which can be used for the determination of trace amounts of monoisotopic elements. (author)

  9. A novel no-reference objective stereoscopic video quality assessment method based on visual saliency analysis

    Science.gov (United States)

    Yang, Xinyan; Zhao, Wei; Ye, Long; Zhang, Qin

    2017-07-01

    This paper proposes a no-reference objective stereoscopic video quality assessment method with the motivation that making the effect of objective experiments close to that of subjective way. We believe that the image regions with different visual salient degree should not have the same weights when designing an assessment metric. Therefore, we firstly use GBVS algorithm to each frame pairs and separate both the left and right viewing images into the regions with strong, general and week saliency. Besides, local feature information like blockiness, zero-crossing and depth are extracted and combined with a mathematical model to calculate a quality assessment score. Regions with different salient degree are assigned with different weights in the mathematical model. Experiment results demonstrate the superiority of our method compared with the existed state-of-the-art no-reference objective Stereoscopic video quality assessment methods.

  10. A frequency domain global parameter estimation method for multiple reference frequency response measurements

    Science.gov (United States)

    Shih, C. Y.; Tsuei, Y. G.; Allemang, R. J.; Brown, D. L.

    1988-10-01

    A method of using the matrix Auto-Regressive Moving Average (ARMA) model in the Laplace domain for multiple-reference global parameter identification is presented. This method is particularly applicable to the area of modal analysis where high modal density exists. The method is also applicable when multiple reference frequency response functions are used to characterise linear systems. In order to facilitate the mathematical solution, the Forsythe orthogonal polynomial is used to reduce the ill-conditioning of the formulated equations and to decouple the normal matrix into two reduced matrix blocks. A Complex Mode Indicator Function (CMIF) is introduced, which can be used to determine the proper order of the rational polynomials.

  11. A Reference Point Construction Method Using Mobile Terminals and the Indoor Localization Evaluation in the Centroid Method

    Directory of Open Access Journals (Sweden)

    Takahiro Yamaguchi

    2015-05-01

    Full Text Available As smartphones become widespread, a variety of smartphone applications are being developed. This paper proposes a method for indoor localization (i.e., positioning that uses only smartphones, which are general-purpose mobile terminals, as reference point devices. This method has the following features: (a the localization system is built with smartphones whose movements are confined to respective limited areas. No fixed reference point devices are used; (b the method does not depend on the wireless performance of smartphones and does not require information about the propagation characteristics of the radio waves sent from reference point devices, and (c the method determines the location at the application layer, at which location information can be easily incorporated into high-level services. We have evaluated the level of localization accuracy of the proposed method by building a software emulator that modeled an underground shopping mall. We have confirmed that the determined location is within a small area in which the user can find target objects visually.

  12. 41Ca standardization by the CIEMAT/NIST LSC method

    International Nuclear Information System (INIS)

    Rodriguez Barquero, L.; Los Arcos, J.M.

    1996-01-01

    A procedure for the liquid scintillation counting standardization of the electron-capture nuclide 41 Ca has been successfully developed and applied with 41 CaCl 2 and 41 Ca-(HDEHP) n samples synthesized in the laboratory from 41 CaCO 3 supplied by Oak Ridge National Laboratory. Six scintillators were tested: the organic samples were stable in toluene-alcohol, Ultima-Gold TM and HiSafe III TM for 30 d, whereas the inorganic samples were only stable in toluene-alcohol and HiSafe III TM for the same period of time. Despite of the low counting efficiencies (1%-13%) due to the very low-energy of less than 3.6 keV of the X-rays and Auger electrons of 41 Ca, the stable samples were standardized by the CIEMAT/NIST method to a combined uncertainty of 2.4% over a range of figures of merit of 1.75 to 7.25 ( 3 H equivalent efficiency of 40% to 7%). (orig.)

  13. Development of the neutron reference calibration field using a {sup 252}Cf standard source surrounded with PMMA moderators

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, T.; Kanai, K.; Tsujimura, N. [Japan Nuclear Cycle Development Institute, Ibaraki-ken (Japan)

    2002-07-01

    The authors developed the neutron reference calibration fields using a {sup 252} Cf standard source surrounded with PMMA moderators at the Japan Nuclear Cycle Development (JNC), Tokai Works. The moderators are co-axial, hollow cylinders made of lead-contained PMMA with a thickness of 13.5, 35.0, 59.5 and 77.0mm, and the {sup 252} Cf source is guided to the geometric center of moderators by the pneumatic system. These fields can provide the moderated neutron spectra very similar to those encountered around the globe-boxes of the fabrication process of MOX (PuO{sub 2}-UO{sub 2} mixed oxide) fuel. The neutron energy spectrum at the reference calibration point was evaluated from the calculations by MCNP4B and the measurements by the INS-type Bonner multi-sphere spectrometer and the hydrogen-filled proportional counters. The calculated neutron spectra were in good agreements with the measured ones. These fields were characterized in terms of the neutron fluence rate, spectral composition and ambient dose equivalent rate, and have served for the response-characterization of various neutron survey instruments.

  14. Development of the neutron reference calibration field using a 252Cf standard source surrounded with PMMA moderators

    International Nuclear Information System (INIS)

    Yoshida, T.; Kanai, K.; Tsujimura, N.

    2002-01-01

    The authors developed the neutron reference calibration fields using a 252 Cf standard source surrounded with PMMA moderators at the Japan Nuclear Cycle Development (JNC), Tokai Works. The moderators are co-axial, hollow cylinders made of lead-contained PMMA with a thickness of 13.5, 35.0, 59.5 and 77.0mm, and the 252 Cf source is guided to the geometric center of moderators by the pneumatic system. These fields can provide the moderated neutron spectra very similar to those encountered around the globe-boxes of the fabrication process of MOX (PuO 2 -UO 2 mixed oxide) fuel. The neutron energy spectrum at the reference calibration point was evaluated from the calculations by MCNP4B and the measurements by the INS-type Bonner multi-sphere spectrometer and the hydrogen-filled proportional counters. The calculated neutron spectra were in good agreements with the measured ones. These fields were characterized in terms of the neutron fluence rate, spectral composition and ambient dose equivalent rate, and have served for the response-characterization of various neutron survey instruments

  15. Standardized methods for Grand Canyon fisheries research 2015

    Science.gov (United States)

    Persons, William R.; Ward, David L.; Avery, Luke A.

    2013-01-01

    This document presents protocols and guidelines to persons sampling fishes in the Grand Canyon, to help ensure consistency in fish handling, fish tagging, and data collection among different projects and organizations. Most such research and monitoring projects are conducted under the general umbrella of the Glen Canyon Dam Adaptive Management Program and include studies by the U.S. Geological Survey (USGS), U.S. Fish and Wildlife Service (FWS), National Park Service (NPS), the Arizona Game and Fish Department (AGFD), various universities, and private contractors. This document is intended to provide guidance to fieldworkers regarding protocols that may vary from year to year depending on specific projects and objectives. We also provide herein documentation of standard methods used in the Grand Canyon that can be cited in scientific publications, as well as a summary of changes in protocols since the document was first created in 2002.

  16. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the PTB and the BIPM

    International Nuclear Information System (INIS)

    Kessler, C.; Allisy-Roberts, P.J.; Selbach, H.J.

    2015-01-01

    An indirect comparison of the standards for reference air kerma rate (RAKR) for 192 Ir high dose rate (HDR) brachytherapy sources of the Physikalisch-Technische Bundesanstalt (PTB), Germany, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the PTB in September 2011. The comparison result, based on the calibration coefficients for a transfer standard and expressed as a ratio of the PTB and the BIPM standards for reference air kerma rate, is 1.0003 with a combined standard uncertainty of 0.0099. (authors)

  17. Reference News Release: U.S. Files Complaint, Announces Settlement to Address Alleged Renewable Fuel Standard Violations by NGL Crude Logistics and Western Dubuque Biodiesel

    Science.gov (United States)

    Reference news release on the complaint against NGL Crude Logistics, LLC and Western Dubuque Biodiesel, LLC and a settlement with Western Dubuque to address alleged violations of the Renewable Fuel Standard.

  18. Standard test method for measurement of soil resistivity using the two-electrode soil box method

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the equipment and a procedure for the measurement of soil resistivity, for samples removed from the ground, for use in the control of corrosion of buried structures. 1.2 Procedures allow for this test method to be used n the field or in the laboratory. 1.3 The test method procedures are for the resistivity measurement of soil samples in the saturated condition and in the as-received condition. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. Soil resistivity values are reported in ohm-centimeter. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.

  19. A quasiparticle-based multi-reference coupled-cluster method.

    Science.gov (United States)

    Rolik, Zoltán; Kállay, Mihály

    2014-10-07

    The purpose of this paper is to introduce a quasiparticle-based multi-reference coupled-cluster (MRCC) approach. The quasiparticles are introduced via a unitary transformation which allows us to represent a complete active space reference function and other elements of an orthonormal multi-reference (MR) basis in a determinant-like form. The quasiparticle creation and annihilation operators satisfy the fermion anti-commutation relations. On the basis of these quasiparticles, a generalization of the normal-ordered operator products for the MR case can be introduced as an alternative to the approach of Mukherjee and Kutzelnigg [Recent Prog. Many-Body Theor. 4, 127 (1995); Mukherjee and Kutzelnigg, J. Chem. Phys. 107, 432 (1997)]. Based on the new normal ordering any quasiparticle-based theory can be formulated using the well-known diagram techniques. Beyond the general quasiparticle framework we also present a possible realization of the unitary transformation. The suggested transformation has an exponential form where the parameters, holding exclusively active indices, are defined in a form similar to the wave operator of the unitary coupled-cluster approach. The definition of our quasiparticle-based MRCC approach strictly follows the form of the single-reference coupled-cluster method and retains several of its beneficial properties. Test results for small systems are presented using a pilot implementation of the new approach and compared to those obtained by other MR methods.

  20. Standard Test Methods for Wet Insulation Integrity Testing of Photovoltaic Modules

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 These test methods provide procedures to determine the insulation resistance of a photovoltaic (PV) module, i.e. the electrical resistance between the module's internal electrical components and its exposed, electrically conductive, non-current carrying parts and surfaces. 1.2 The insulation integrity procedures are a combination of wet insulation resistance and wet dielectric voltage withstand test procedures. 1.3 These procedures are similar to and reference the insulation integrity test procedures described in Test Methods E 1462, with the difference being that the photovoltaic module under test is immersed in a wetting solution during the procedures. 1.4 These test methods do not establish pass or fail levels. The determination of acceptable or unacceptable results is beyond the scope of these test methods. 1.5 The values stated in SI units are to be regarded as the standard. 1.6 There is no similar or equivalent ISO standard. 1.7 This standard does not purport to address all of the safety conce...

  1. Microbleed detection using automated segmentation (MIDAS): a new method applicable to standard clinical MR images.

    Science.gov (United States)

    Seghier, Mohamed L; Kolanko, Magdalena A; Leff, Alexander P; Jäger, Hans R; Gregoire, Simone M; Werring, David J

    2011-03-23

    Cerebral microbleeds, visible on gradient-recalled echo (GRE) T2* MRI, have generated increasing interest as an imaging marker of small vessel diseases, with relevance for intracerebral bleeding risk or brain dysfunction. Manual rating methods have limited reliability and are time-consuming. We developed a new method for microbleed detection using automated segmentation (MIDAS) and compared it with a validated visual rating system. In thirty consecutive stroke service patients, standard GRE T2* images were acquired and manually rated for microbleeds by a trained observer. After spatially normalizing each patient's GRE T2* images into a standard stereotaxic space, the automated microbleed detection algorithm (MIDAS) identified cerebral microbleeds by explicitly incorporating an "extra" tissue class for abnormal voxels within a unified segmentation-normalization model. The agreement between manual and automated methods was assessed using the intraclass correlation coefficient (ICC) and Kappa statistic. We found that MIDAS had generally moderate to good agreement with the manual reference method for the presence of lobar microbleeds (Kappa = 0.43, improved to 0.65 after manual exclusion of obvious artefacts). Agreement for the number of microbleeds was very good for lobar regions: (ICC = 0.71, improved to ICC = 0.87). MIDAS successfully detected all patients with multiple (≥2) lobar microbleeds. MIDAS can identify microbleeds on standard MR datasets, and with an additional rapid editing step shows good agreement with a validated visual rating system. MIDAS may be useful in screening for multiple lobar microbleeds.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Method and platform standardization in MRM-based quantitative plasma proteomics.

    Science.gov (United States)

    Percy, Andrew J; Chambers, Andrew G; Yang, Juncong; Jackson, Angela M; Domanski, Dominik; Burkhart, Julia; Sickmann, Albert; Borchers, Christoph H

    2013-12-16

    There exists a growing demand in the proteomics community to standardize experimental methods and liquid chromatography-mass spectrometry (LC/MS) platforms in order to enable the acquisition of more precise and accurate quantitative data. This necessity is heightened by the evolving trend of verifying and validating candidate disease biomarkers in complex biofluids, such as blood plasma, through targeted multiple reaction monitoring (MRM)-based approaches with stable isotope-labeled standards (SIS). Considering the lack of performance standards for quantitative plasma proteomics, we previously developed two reference kits to evaluate the MRM with SIS peptide approach using undepleted and non-enriched human plasma. The first kit tests the effectiveness of the LC/MRM-MS platform (kit #1), while the second evaluates the performance of an entire analytical workflow (kit #2). Here, these kits have been refined for practical use and then evaluated through intra- and inter-laboratory testing on 6 common LC/MS platforms. For an identical panel of 22 plasma proteins, similar concentrations were determined, regardless of the kit, instrument platform, and laboratory of analysis. These results demonstrate the value of the kit and reinforce the utility of standardized methods and protocols. The proteomics community needs standardized experimental protocols and quality control methods in order to improve the reproducibility of MS-based quantitative data. This need is heightened by the evolving trend for MRM-based validation of proposed disease biomarkers in complex biofluids such as blood plasma. We have developed two kits to assist in the inter- and intra-laboratory quality control of MRM experiments: the first kit tests the effectiveness of the LC/MRM-MS platform (kit #1), while the second evaluates the performance of an entire analytical workflow (kit #2). In this paper, we report the use of these kits in intra- and inter-laboratory testing on 6 common LC/MS platforms. This

  4. Matrix pencil method-based reference current generation for shunt active power filters

    DEFF Research Database (Denmark)

    Terriche, Yacine; Golestan, Saeed; Guerrero, Josep M.

    2018-01-01

    response and works well under distorted and unbalanced voltage. Moreover, the proposed method can estimate the voltage phase accurately; this property enables the algorithm to compensate for both power factor and current unbalance. The effectiveness of the proposed method is verified using simulation...... are using the discrete Fourier transform (DFT) in the frequency domain or the instantaneous p–q theory and the synchronous reference frame in the time domain. The DFT, however, suffers from the picket-fence effect and spectral leakage. On the other hand, the DFT takes at least one cycle of the nominal...... frequency. The time-domain methods show a weakness under voltage distortion, which requires prior filtering techniques. The aim of this study is to present a fast yet effective method for generating the RCC for SAPFs. The proposed method, which is based on the matrix pencil method, has a fast dynamic...

  5. Precision and Accuracy of k0-NAA Method for Analysis of Multi Elements in Reference Samples

    International Nuclear Information System (INIS)

    Sri-Wardani

    2004-01-01

    Accuracy and precision of k 0 -NAA method could determine in the analysis of multi elements contained in reference samples. The analyzed results of multi elements in SRM 1633b sample were obtained with optimum results in bias of 20% but it is in a good accuracy and precision. The analyzed results of As, Cd and Zn in CCQM-P29 rice flour sample were obtained with very good result in bias of 0.5 - 5.6%. (author)

  6. The complementary use of radioanalytical methods and trace analysis methods for the characterisation of environmental IAEA reference materials

    International Nuclear Information System (INIS)

    De Regge, P.; Burns, K.; Campbell, M.; Makarewicz, M.; Markowicz, A.; Mattiuzzi, M.; Tajani, A.; Toervenyi, A.; Zeiller, E.

    2001-01-01

    The IAEA laboratories have access to both nuclear analytical methods and conventional instrumental methods for trace analysis for the characterisation of its environmental and biological reference materials. A technical concept integrating the homogeneity data, the recommended test portion mass and the uncertainty on the trace element concentrations is explored using a combination of INAA, XRF, ICP-MS, ICP-AES, and AAS. The above approach is illustrated by selected examples of reference materials currently under evaluation for their trace element content. They include some or all of the following elements Al, As, Br, Ca, Cd, Co, Cr, Cs, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Rb, Se, Sr, Th, U, Zn in environmental biomonitor organisms (lichen, algae) and air dust filters. (author)

  7. Identification of reliable gridded reference data for statistical downscaling methods in Alberta

    Science.gov (United States)

    Eum, H. I.; Gupta, A.

    2017-12-01

    Climate models provide essential information to assess impacts of climate change at regional and global scales. However, statistical downscaling methods have been applied to prepare climate model data for various applications such as hydrologic and ecologic modelling at a watershed scale. As the reliability and (spatial and temporal) resolution of statistically downscaled climate data mainly depend on a reference data, identifying the most reliable reference data is crucial for statistical downscaling. A growing number of gridded climate products are available for key climate variables which are main input data to regional modelling systems. However, inconsistencies in these climate products, for example, different combinations of climate variables, varying data domains and data lengths and data accuracy varying with physiographic characteristics of the landscape, have caused significant challenges in selecting the most suitable reference climate data for various environmental studies and modelling. Employing various observation-based daily gridded climate products available in public domain, i.e. thin plate spline regression products (ANUSPLIN and TPS), inverse distance method (Alberta Townships), and numerical climate model (North American Regional Reanalysis) and an optimum interpolation technique (Canadian Precipitation Analysis), this study evaluates the accuracy of the climate products at each grid point by comparing with the Adjusted and Homogenized Canadian Climate Data (AHCCD) observations for precipitation, minimum and maximum temperature over the province of Alberta. Based on the performance of climate products at AHCCD stations, we ranked the reliability of these publically available climate products corresponding to the elevations of stations discretized into several classes. According to the rank of climate products for each elevation class, we identified the most reliable climate products based on the elevation of target points. A web-based system

  8. Instrumental neutron activation analysis of river habitants by the k(0)-standardization method

    International Nuclear Information System (INIS)

    Momoshima, N.; Toyoshima, T.; Matsushita, R.; Fukuda, A.; Hibino, K.

    2005-01-01

    Analysis of metal concentrations in samples use reference materials for determination, which means elements out of the references are not possible to be determined. The instrumental neutron activation analysis (INAA) with k(O)-standardization method makes possible to determine metals without use of reference materials, which is very attractive for environmental sample analysis, River habitants would be available as a bio-indicator from which river water quality or metal contamination level could be evaluated. We analyzed river fishes and river insects by INAA with k(O)-standardization to examine the possibility of these habitants as a bio-indicator of water system. Small fishes, Oryzias latipes and Gambusia affinis were collected at 3 different rivers every month and river insects, families of Heptageniidae, Baetidae, Perlidae, Hydropsychidae, Psephenidae were collected at a fixed point of the river. The dried samples were irradiated at the research reactor, JRR-4 (3.5MW), JAERI for 10 min and 3 h. 17 elements (Na, K, Ca, Sc, Cr, Mn, Fe, Co, Zn, As, Se, Br, Rb, Sr, Ba, Ce and Sm) were determined by the NAA-k(0) method, showing effectiveness of the present method for environmental sample analysis. The metals observed in the fishes were the highest in Ca and the lowest in Sc, ranging from 10 5 mg/kg-dry weigh in Ca to 10 -2 mg/kg-dry weight in Sc. The differences in metal concentrations were examined by statistical analysis with t-test. Ca, Na and Br concentrations differ between species, Oryzias latipes and Gambusia, and Fe, Sc, Co, Zn and Se concentrations differ among rivers. No difference was observed on K, Rb and Sr concentrations.

  9. Comparing the role of standard references on the prevalence of Iranian children and adolescents' overweight and obesity: A systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Saeed Ghanbari

    2016-01-01

    Full Text Available Background: Obesity is a major risk factor for chronic diseases and has a role on high blood pressure, diabetes type II, etc., This review assesses the prevalence of Iranian children obesity and overweight for different age categories and compares the three standard definitions of obesity. Materials and Methods: To retrieve desirable studies concerning childhood anthropometric data from different area of Iran, the MEDLINE, Scopus, and different local databases such as Scientific Information database were used. The studies reported the prevalence of obesity or overweight of children < 6, 6–12, and 12–20 years old, despite differences between definitions of childhood obesity, were included in the study. We combined the reported prevalence of the overweight and obesity with regard to age and gender, and also by the different standard references which are the Centers for Disease Control and Prevention (CDC, the World Health Organization (WHO definition, and the International Obesity Task Force (IOTF references. The analysis was carried out using STATA software. Results: Our review covered 75 articles reported the prevalence of overweight or obesity among children and adolescents for different age groups in Iran. Our meta-regression analysis showed that the prevalence of obesity and overweight did not vary significantly in gender and age categories, but different definitions provide different prevalence of overweight and obesity. Conclusion: The effective factors on obesity and overweight included administration policy and organizational, interpersonal, intrapersonal, and social factors. CDC and WHO references intended in monitoring children's growth and the IOTF cutoffs would rather provide a common set of definitions that researchers and policymakers could use for descriptive and comparative purposes.

  10. Comparison of two different segmentation methods on planar lung perfusion scan with reference to quantitative value on SPECT/CT

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Min Seok; Kang, Yeon Koo; Ha, Seung Gyun [Dept. of Nuclear Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); and others

    2017-06-15

    Until now, there was no single standardized regional segmentation method of planar lung perfusion scan. We compared planar scan based two segmentation methods, which are frequently used in the Society of Nuclear Medicine, with reference to the lung perfusion single photon emission computed tomography (SPECT)/computed tomography (CT) derived values in lung cancer patients. Fifty-five lung cancer patients (male:female, 37:18; age, 67.8 ± 10.7 years) were evaluated. The patients underwent planar scan and SPECT/CT after injection of technetium-99 m macroaggregated albumin (Tc-99 m-MAA). The % uptake and predicted postoperative percentage forced expiratory volume in 1 s (ppoFEV1%) derived from both posterior oblique (PO) and anterior posterior (AP) methods were compared with SPECT/CT derived parameters. Concordance analysis, paired comparison, reproducibility analysis and spearman correlation analysis were conducted. The % uptake derived from PO method showed higher concordance with SPECT/CT derived % uptake in every lobe compared to AP method. Both methods showed significantly different lobar distribution of % uptake compared to SPECT/CT. For the target region, ppoFEV1% measured from PO method showed higher concordance with SPECT/CT, but lower reproducibility compared to AP method. Preliminary data revealed that every method significantly correlated with actual postoperative FEV1%, with SPECT/CT showing the best correlation. The PO method derived values showed better concordance with SPECT/CT compared to the AP method. Both PO and AP methods showed significantly different lobar distribution compared to SPECT/CT. In clinical practice such difference according to different methods and lobes should be considered for more accurate postoperative lung function prediction.

  11. Accurate determination of arsenic in arsenobetaine standard solutions of BCR-626 and NMIJ CRM 7901-a by neutron activation analysis coupled with internal standard method.

    Science.gov (United States)

    Miura, Tsutomu; Chiba, Koichi; Kuroiwa, Takayoshi; Narukawa, Tomohiro; Hioki, Akiharu; Matsue, Hideaki

    2010-09-15

    Neutron activation analysis (NAA) coupled with an internal standard method was applied for the determination of As in the certified reference material (CRM) of arsenobetaine (AB) standard solutions to verify their certified values. Gold was used as an internal standard to compensate for the difference of the neutron exposure in an irradiation capsule and to improve the sample-to-sample repeatability. Application of the internal standard method significantly improved linearity of the calibration curve up to 1 microg of As, too. The analytical reliability of the proposed method was evaluated by k(0)-standardization NAA. The analytical results of As in AB standard solutions of BCR-626 and NMIJ CRM 7901-a were (499+/-55)mgkg(-1) (k=2) and (10.16+/-0.15)mgkg(-1) (k=2), respectively. These values were found to be 15-20% higher than the certified values. The between-bottle variation of BCR-626 was much larger than the expanded uncertainty of the certified value, although that of NMIJ CRM 7901-a was almost negligible. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  12. Improvements in the equipment for determination of Kr-85 with the reference method

    International Nuclear Information System (INIS)

    Heras Iniquez, M.C.; Perez Garcia, M.M.

    1983-01-01

    A new equipment for Kr-85 separation and their cryogenic chromatographic concentration is described, which presents some advantages respect the equipment used as reference. The new apparatus, made with metallic elements, is based on the method of concentration and separation previously described but presents easier control, faster chromatographic separations and without loosed of efficiency and reproducibility that the previous one. The concentration and separation procedure for Kr-85 and a comparative study between both apparatus is described. Also the efficiency of the method is obtained experimentally. (Author)

  13. Method of collective variables with reference system for the grand canonical ensemble

    International Nuclear Information System (INIS)

    Yukhnovskii, I.R.

    1989-01-01

    A method of collective variables with special reference system for the grand canonical ensemble is presented. An explicit form is obtained for the basis sixth-degree measure density needed to describe the liquid-gas phase transition. Here the author presents the fundamentals of the method, which are as follows: (1) the functional form for the partition function in the grand canonical ensemble; (2) derivation of thermodynamic relations for the coefficients of the Jacobian; (3) transition to the problem on an adequate lattice; and (4) obtaining of the explicit form for the functional of the partition function

  14. Reducing matrix effect error in EDXRF: Comparative study of using standard and standard less methods for stainless steel samples

    International Nuclear Information System (INIS)

    Meor Yusoff Meor Sulaiman; Masliana Muhammad; Wilfred, P.

    2013-01-01

    Even though EDXRF analysis has major advantages in the analysis of stainless steel samples such as simultaneous determination of the minor elements, analysis can be done without sample preparation and non-destructive analysis, the matrix issue arise from the inter element interaction can make the the final quantitative result to be in accurate. The paper relates a comparative quantitative analysis using standard and standard less methods in the determination of these elements. Standard method was done by plotting regression calibration graphs of the interested elements using BCS certified stainless steel standards. Different calibration plots were developed based on the available certified standards and these stainless steel grades include low alloy steel, austenitic, ferritic and high speed. The standard less method on the other hand uses a mathematical modelling with matrix effect correction derived from Lucas-Tooth and Price model. Further improvement on the accuracy of the standard less method was done by inclusion of pure elements into the development of the model. Discrepancy tests were then carried out for these quantitative methods on different certified samples and the results show that the high speed method is most reliable for determining of Ni and the standard less method for Mn. (Author)

  15. New Normative Database of Inner Macular Layer Thickness Measured by Spectralis OCT Used as Reference Standard for Glaucoma Detection.

    Science.gov (United States)

    Nieves-Moreno, María; Martínez-de-la-Casa, José M; Bambo, María P; Morales-Fernández, Laura; Van Keer, Karel; Vandewalle, Evelien; Stalmans, Ingeborg; García-Feijoó, Julián

    2018-02-01

    This study examines the capacity to detect glaucoma of inner macular layer thickness measured by spectral-domain optical coherence tomography (SD-OCT) using a new normative database as the reference standard. Participants ( N = 148) were recruited from Leuven (Belgium) and Zaragoza (Spain): 74 patients with early/moderate glaucoma and 74 age-matched healthy controls. One eye was randomly selected for a macular scan using the Spectralis SD-OCT. The variables measured with the instrument's segmentation software were: macular nerve fiber layer (mRNFL), ganglion cell layer (GCL), and inner plexiform layer (IPL) volume and thickness along with circumpapillary RNFL thickness (cpRNFL). The new normative database of macular variables was used to define the cutoff of normality as the fifth percentile by age group. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) of each macular measurement and of cpRNFL were used to distinguish between patients and controls. Overall sensitivity and specificity to detect early-moderate glaucoma were 42.2% and 88.9% for mRNFL, 42.4% and 95.6% for GCL, 42.2% and 94.5% for IPL, and 53% and 94.6% for RNFL, respectively. The best macular variable to discriminate between the two groups of subjects was outer temporal GCL thickness as indicated by an AUROC of 0.903. This variable performed similarly to mean cpRNFL thickness (AUROC = 0.845; P = 0.29). Using our normative database as reference, the diagnostic power of inner macular layer thickness proved comparable to that of peripapillary RNFL thickness. Spectralis SD-OCT, cpRNFL thickness, and individual macular inner layer thicknesses show comparable diagnostic capacity for glaucoma and RNFL, GCL, and IPL thickness may be useful as an alternative diagnostic test when the measure of cpRNFL shows artifacts.

  16. Resampling Approach for Determination of the Method for Reference Interval Calculation in Clinical Laboratory Practice▿

    Science.gov (United States)

    Pavlov, Igor Y.; Wilson, Andrew R.; Delgado, Julio C.

    2010-01-01

    Reference intervals (RI) play a key role in clinical interpretation of laboratory test results. Numerous articles are devoted to analyzing and discussing various methods of RI determination. The two most widely used approaches are the parametric method, which assumes data normality, and a nonparametric, rank-based procedure. The decision about which method to use is usually made arbitrarily. The goal of this study was to demonstrate that using a resampling approach for the comparison of RI determination techniques could help researchers select the right procedure. Three methods of RI calculation—parametric, transformed parametric, and quantile-based bootstrapping—were applied to multiple random samples drawn from 81 values of complement factor B observations and from a computer-simulated normally distributed population. It was shown that differences in RI between legitimate methods could be up to 20% and even more. The transformed parametric method was found to be the best method for the calculation of RI of non-normally distributed factor B estimations, producing an unbiased RI and the lowest confidence limits and interquartile ranges. For a simulated Gaussian population, parametric calculations, as expected, were the best; quantile-based bootstrapping produced biased results at low sample sizes, and the transformed parametric method generated heavily biased RI. The resampling approach could help compare different RI calculation methods. An algorithm showing a resampling procedure for choosing the appropriate method for RI calculations is included. PMID:20554803

  17. Ambulatory Blood Pressure Monitoring (ABPM) as the reference standard for diagnosis of hypertension and assessment of vascular risk in adults.

    Science.gov (United States)

    Hermida, Ramón C; Smolensky, Michael H; Ayala, Diana E; Portaluppi, Francesco

    2015-01-01

    New information has become available since the ISC, AAMCC, and SECAC released their first extensive guidedelines to improve the diagnosis and treatment of adult arterial hypertension. A critical assessment of evidence and a comparison of what international guidelines now propose are the basis for the following statements, which update the recommendations first issued in 2013. Office blood pressure (BP) measurements should no longer be considered to be the "gold standard" for the diagnosis of hypertension and assessment of cardiovascular risk. Relying on office BP, even when supplemented with at-home wake-time self-measurements, to identify high-risk individuals, disregarding circadian BP patterning and asleep BP level, leads to potential misclassification of 50% of all evaluated persons. Accordingly, ambulatory BP monitoring is the recommended reference standard for the diagnosis of true hypertension and accurate assessment of cardiovascular risk in all adults ≥18 yrs of age, regardless of whether office BP is normal or elevated. Asleep systolic BP mean is the most significant independent predictor of cardiovascular events. The sleep-time relative SBP decline adds prognostic value to the statistical model that already includes the asleep systolic BP mean and corrected for relevant confounding variables. Accordingly, the asleep systolic BP mean is the recommended protocol to diagnose hypertension, assess cardiovascular risk, and predict cardiovascular event-free interval. In men, and in the absence of compelling clinical conditions, reference thresholds for diagnosing hypertension are 120/70 mmHg for the asleep systolic/diastolic BP means derived from ambulatory BP monitoring. However, in women, in the absence of complicating co-morbidities, the same thresholds are lower by 10/5 mmHg, i.e., 110/65 mmHg for the asleep means. In high-risk patients, including those diagnosed with diabetes or chronic kidney disease, and/or those having experienced past

  18. Reference voltage calculation method based on zero-sequence component optimisation for a regional compensation DVR

    Science.gov (United States)

    Jian, Le; Cao, Wang; Jintao, Yang; Yinge, Wang

    2018-04-01

    This paper describes the design of a dynamic voltage restorer (DVR) that can simultaneously protect several sensitive loads from voltage sags in a region of an MV distribution network. A novel reference voltage calculation method based on zero-sequence voltage optimisation is proposed for this DVR to optimise cost-effectiveness in compensation of voltage sags with different characteristics in an ungrounded neutral system. Based on a detailed analysis of the characteristics of voltage sags caused by different types of faults and the effect of the wiring mode of the transformer on these characteristics, the optimisation target of the reference voltage calculation is presented with several constraints. The reference voltages under all types of voltage sags are calculated by optimising the zero-sequence component, which can reduce the degree of swell in the phase-to-ground voltage after compensation to the maximum extent and can improve the symmetry degree of the output voltages of the DVR, thereby effectively increasing the compensation ability. The validity and effectiveness of the proposed method are verified by simulation and experimental results.

  19. A Method for Developing Standard Patient Education Program.

    Science.gov (United States)

    Lura, Carolina Bryne; Hauch, Sophie Misser Pallesgaard; Gøeg, Kirstine Rosenbeck; Pape-Haugaard, Louise

    2018-01-01

    In Denmark, patients being treated on Haematology Outpatients Departments get instructed to self-manage their blood sample collection from Central Venous Catheter (CVC). However, this is a complex and risky procedure, which can jeopardize patient safety. The aim of the study was to suggest a method for developing standard digital patient education programs for patients in self-administration of blood samples drawn from CVC. The Design Science Research Paradigm was used to develop a digital patient education program, called PAVIOSY, to increase patient safety during execution of the blood sample collection procedure by using videos for teaching as well as procedural support. A step-by-step guide was developed and used as basis for making the videos. Quality assurance through evaluation with a nurse was conducted on both the step-by-step guide and the videos. The quality assurance evaluation of the videos showed; 1) Errors due to the order of the procedure can be determined by reviewing the videos despite that the guide was followed. 2) Videos can be used to identify errors - important for patient safety - in the procedure, which are not identifiable in a written script. To ensure correct clinical content of the educational patient system, health professionals must be engaged early in the development of content and design phase.

  20. Substoichiometric isotope dilution analysis of arsenic in biological and environmental standard reference materials by solvent extraction using toluene-3,4-dithiol in benzene

    International Nuclear Information System (INIS)

    Chutke, N.L.; Ambulkar, Ms.M.N.; Weginwar, R.G.; Garg, A.N.

    1994-01-01

    A radiochemical solvent extraction procedure has been developed for the determination of As(III) using 76 As tracer. It is based on the complexation of As(III) with toluene-3,4-dithiol (TDT) at pH 2 and subsequent extraction in benzene. The effect of various parameters such as pH, time of equilibration, nature of solvent, quantitative character and interferences have been studied. The method has been further developed into substoichiometric isotope dilution analysis for the determination of As at < 1μg level and employed for the analysis of several environmental and biological standard Reference Materials from NIST (USA), IAEA (Vienna) and NIES (Japan). (author) 39 refs.; 4 figs.; 4 tabs

  1. Reference standards for quantitative trace analysis of PCB's by GC. Technical PCB formulations for the calibration of ECD and MSD responses

    Energy Technology Data Exchange (ETDEWEB)

    Krupcik, J. (Slovak Technical Univ., Department of Analytical Chemistry, Bratislava (Slovakia)); Kocan, A. (Institute of Preventive Medicine, Bratislava (Slovakia)); Petrik, J. (Institute of Preventive Medicine, Bratislava (Slovakia)); Leclercq, P.A. (Eindhoven University of Technology, Dept. of Chemical Engineering, Lab. of Instrumental Analysis (Netherlands)); Ballschmiter, K. (University of Ulm, Dept. of Analytical and Environmental Chemistry (Germany))

    1993-04-01

    The composition of any technical PCB formulation can be determined directly by analyzing the PCB sample by gas chromatography with a flame ionization detector (GC-FID), provided the relative molecular masses of the components are known. The response of electron capture and selected-ion monitoring, mass-spectra detectors can then be calibrated for individual PCB congeners by correlation of the chromatographic patterns with those of concentrated PCB samples obtained by GC-FID. This procedure, which uses a given technical PCB formulation as a secondary reference standard mixture, is to be preferred over existing calibration methods, when results with [+-]10% errors are acceptable because commercial PCB formulations cover the whole range of chlorination products. (orig.)

  2. A simple and effective method to achieve the successful start-up of a current reference

    International Nuclear Information System (INIS)

    Han Lei; Zhang Xiaoxing; Dai Yujie; Lü Yingjie; Wang Yujun

    2012-01-01

    Start-up design is a critical issue in current reference as it is very closely related to production yield. However, its function is difficult to predict using normal transaction simulations before the device is put into diffusion. In this paper, we discuss a simple and effective simulation approach which ensures a successful start-up process in a self-biased temperature independent current reference. The circuit is implemented in a class-D power amplifier with a 0.35 μm BiCMOS process and the experimental result validates that, by using this method, the start-up success rate can be greatly improved to 100%. (semiconductor integrated circuits)

  3. [Precautions of physical performance requirements and test methods during product standard drafting process of medical devices].

    Science.gov (United States)

    Song, Jin-Zi; Wan, Min; Xu, Hui; Yao, Xiu-Jun; Zhang, Bo; Wang, Jin-Hong

    2009-09-01

    The major idea of this article is to discuss standardization and normalization for the product standard of medical devices. Analyze the problem related to the physical performance requirements and test methods during product standard drafting process and make corresponding suggestions.

  4. An internal reference model-based PRF temperature mapping method with Cramer-Rao lower bound noise performance analysis.

    Science.gov (United States)

    Li, Cheng; Pan, Xinyi; Ying, Kui; Zhang, Qiang; An, Jing; Weng, Dehe; Qin, Wen; Li, Kuncheng

    2009-11-01

    The conventional phase difference method for MR thermometry suffers from disturbances caused by the presence of lipid protons, motion-induced error, and field drift. A signal model is presented with multi-echo gradient echo (GRE) sequence using a fat signal as an internal reference to overcome these problems. The internal reference signal model is fit to the water and fat signals by the extended Prony algorithm and the Levenberg-Marquardt algorithm to estimate the chemical shifts between water and fat which contain temperature information. A noise analysis of the signal model was conducted using the Cramer-Rao lower bound to evaluate the noise performance of various algorithms, the effects of imaging parameters, and the influence of the water:fat signal ratio in a sample on the temperature estimate. Comparison of the calculated temperature map and thermocouple temperature measurements shows that the maximum temperature estimation error is 0.614 degrees C, with a standard deviation of 0.06 degrees C, confirming the feasibility of this model-based temperature mapping method. The influence of sample water:fat signal ratio on the accuracy of the temperature estimate is evaluated in a water-fat mixed phantom experiment with an optimal ratio of approximately 0.66:1. (c) 2009 Wiley-Liss, Inc.

  5. Evaluation of serological diagnostic tests for typhoid fever in Papua New Guinea using a composite reference standard.

    Science.gov (United States)

    Siba, Valentine; Horwood, Paul F; Vanuga, Kilagi; Wapling, Johanna; Sehuko, Rebecca; Siba, Peter M; Greenhill, Andrew R

    2012-11-01

    Typhoid fever remains a major global health problem. A major impediment to improving outcomes is the lack of appropriate diagnostic tools, which have not significantly improved in low-income settings for 100 years. We evaluated two commercially available rapid diagnostic tests (Tubex and TyphiDot), a prototype (TyphiRapid TR-02), and the commonly used single-serum Widal test in a previously reported high-burden area of Papua New Guinea. Samples were collected from 530 outpatients with axillary temperatures of ≥37.5°C, and analysis was conducted on all malaria-negative samples (n = 500). A composite reference standard of blood culture and PCR was used, by which 47 participants (9.4%) were considered typhoid fever positive. The sensitivity and specificity of the Tubex (51.1% and 88.3%, respectively) and TyphiDot (70.0% and 80.1%, respectively) tests were not high enough to warrant their ongoing use in this setting; however, the sensitivity and specificity for the TR-02 prototype were promising (89.4% and 85.0%, respectively). An axillary temperature of ≥38.5°C correlated with typhoid fever (P = 0.014). With an appropriate diagnostic test, conducting typhoid fever diagnosis only on patients with high-grade fever could dramatically decrease the costs associated with diagnosis while having no detrimental impact on the ability to accurately diagnose the illness.

  6. KoVariome: Korean National Standard Reference Variome database of whole genomes with comprehensive SNV, indel, CNV, and SV analyses.

    Science.gov (United States)

    Kim, Jungeun; Weber, Jessica A; Jho, Sungwoong; Jang, Jinho; Jun, JeHoon; Cho, Yun Sung; Kim, Hak-Min; Kim, Hyunho; Kim, Yumi; Chung, OkSung; Kim, Chang Geun; Lee, HyeJin; Kim, Byung Chul; Han, Kyudong; Koh, InSong; Chae, Kyun Shik; Lee, Semin; Edwards, Jeremy S; Bhak, Jong

    2018-04-04

    High-coverage whole-genome sequencing data of a single ethnicity can provide a useful catalogue of population-specific genetic variations, and provides a critical resource that can be used to more accurately identify pathogenic genetic variants. We report a comprehensive analysis of the Korean population, and present the Korean National Standard Reference Variome (KoVariome). As a part of the Korean Personal Genome Project (KPGP), we constructed the KoVariome database using 5.5 terabases of whole genome sequence data from 50 healthy Korean individuals in order to characterize the benign ethnicity-relevant genetic variation present in the Korean population. In total, KoVariome includes 12.7M single-nucleotide variants (SNVs), 1.7M short insertions and deletions (indels), 4K structural variations (SVs), and 3.6K copy number variations (CNVs). Among them, 2.4M (19%) SNVs and 0.4M (24%) indels were identified as novel. We also discovered selective enrichment of 3.8M SNVs and 0.5M indels in Korean individuals, which were used to filter out 1,271 coding-SNVs not originally removed from the 1,000 Genomes Project when prioritizing disease-causing variants. KoVariome health records were used to identify novel disease-causing variants in the Korean population, demonstrating the value of high-quality ethnic variation databases for the accurate interpretation of individual genomes and the precise characterization of genetic variations.

  7. MRI screening for silicone breast implant rupture: accuracy, inter- and intraobserver variability using explantation results as reference standard

    Energy Technology Data Exchange (ETDEWEB)

    Maijers, M.C.; Ritt, M.J.P.F. [VU University Medical Centre, Department of Plastic, Reconstructive and Hand Surgery, De Boelelaan 1117, PO Box 7057, Amsterdam (Netherlands); Niessen, F.B. [VU University Medical Centre, Department of Plastic, Reconstructive and Hand Surgery, De Boelelaan 1117, PO Box 7057, Amsterdam (Netherlands); Jan van Goyen Clinic, Department of Plastic Surgery, Amsterdam (Netherlands); Veldhuizen, J.F.H. [MRI Centre, Amsterdam (Netherlands); Manoliu, R.A. [MRI Centre, Amsterdam (Netherlands); VU University Medical Centre, Department of Radiology, Amsterdam (Netherlands)

    2014-06-15

    The recall of Poly Implant Prothese (PIP) silicone breast implants in 2010 resulted in large numbers of asymptomatic women with implants who underwent magnetic resonance imaging (MRI) screening. This study's aim was to assess the accuracy and interobserver variability of MRI screening in the detection of rupture and extracapsular silicone leakage. A prospective study included 107 women with 214 PIP implants who underwent explantation preceded by MRI. In 2013, two radiologists blinded for previous MRI findings or outcome at surgery, independently re-evaluated all MRI examinations. A structured protocol described the MRI findings. The ex vivo findings served as reference standard. In 208 of the 214 explanted prostheses, radiologists agreed independently about the condition of the implants. In five of the six cases they disagreed (2.6 %), but subsequently reached consensus. A sensitivity of 93 %, specificity of 93 %, positive predictive value of 77 % and negative predictive value of 98 % was found. The interobserver agreement was excellent (kappa value of 0.92). MRI has a high accuracy in diagnosing rupture in silicone breast implants. Considering the high kappa value of interobserver agreement, MRI appears to be a consistent diagnostic test. A simple, uniform classification, may improve communication between radiologist and plastic surgeon. (orig.)

  8. MRI screening for silicone breast implant rupture: accuracy, inter- and intraobserver variability using explantation results as reference standard

    International Nuclear Information System (INIS)

    Maijers, M.C.; Ritt, M.J.P.F.; Niessen, F.B.; Veldhuizen, J.F.H.; Manoliu, R.A.

    2014-01-01

    The recall of Poly Implant Prothese (PIP) silicone breast implants in 2010 resulted in large numbers of asymptomatic women with implants who underwent magnetic resonance imaging (MRI) screening. This study's aim was to assess the accuracy and interobserver variability of MRI screening in the detection of rupture and extracapsular silicone leakage. A prospective study included 107 women with 214 PIP implants who underwent explantation preceded by MRI. In 2013, two radiologists blinded for previous MRI findings or outcome at surgery, independently re-evaluated all MRI examinations. A structured protocol described the MRI findings. The ex vivo findings served as reference standard. In 208 of the 214 explanted prostheses, radiologists agreed independently about the condition of the implants. In five of the six cases they disagreed (2.6 %), but subsequently reached consensus. A sensitivity of 93 %, specificity of 93 %, positive predictive value of 77 % and negative predictive value of 98 % was found. The interobserver agreement was excellent (kappa value of 0.92). MRI has a high accuracy in diagnosing rupture in silicone breast implants. Considering the high kappa value of interobserver agreement, MRI appears to be a consistent diagnostic test. A simple, uniform classification, may improve communication between radiologist and plastic surgeon. (orig.)

  9. Relation of structure to function for the US reference standard endotoxin after exposure to 60Co radiation

    International Nuclear Information System (INIS)

    Csako, G.; Suba, E.A.; Ahlgren, A.; Tsai, C.M.; Elin, R.J.

    1986-01-01

    The structure and function of the highly purified US reference standard endotoxin (RSE) were studied after exposure to ionizing radiation from a 60 Co source. With increasing doses of radiation, the trilaminar ribbon-like structure of untreated endotoxin exhibited focal swelling, after which only spherical particles were seen by electron microscopy. These morphological changes were paralleled by the respective loss of O-side chain repeating units and pieces of the R-core from the lipopolysaccharide molecules, as demonstrated by electrophoresis. The biologic function of the irradiated endotoxin was assessed with a variety of tests. At higher doses of radiation, a direct relation was observed between the degradation of the molecular and supramolecular structure and the loss of biologic function. At lower doses of radiation, however, there was variability among the functional assays in their rate of change with progressive irradiation of the RSE. The results suggest that the carbohydrate moiety plays an important role both in determining the supramolecular structure and in modulating certain biologic activities of bacterial endotoxins

  10. Lung function in North American Indian children: reference standards for spirometry, maximal expiratory flow volume curves, and peak expiratory flow.

    Science.gov (United States)

    Wall, M A; Olson, D; Bonn, B A; Creelman, T; Buist, A S

    1982-02-01

    Reference standards of lung function was determined in 176 healthy North American Indian children (94 girls, 82 boys) 7 to 18 yr of age. Spirometry, maximal expiratory flow volume curves, and peak expiratory flow rate were measured using techniques and equipment recommended by the American Thoracic Society. Standing height was found to be an accurate predictor of lung function, and prediction equations for each lung function variable are presented using standing height as the independent variable. Lung volumes and expiratory flow rates in North American Indian children were similar to those previously reported for white and Mexican-American children but were greater than those in black children. In both boys and girls, lung function increased in a curvilinear fashion. Volume-adjusted maximal expiratory flow rates after expiring 50 or 75% of FVC tended to decrease in both sexes as age and height increased. Our maximal expiratory flow volume curve data suggest that as North American Indian children grow, lung volume increases at a slightly faster rate than airway size does.

  11. Bayesian modeling and inference for diagnostic accuracy and probability of disease based on multiple diagnostic biomarkers with and without a perfect reference standard.

    Science.gov (United States)

    Jafarzadeh, S Reza; Johnson, Wesley O; Gardner, Ian A

    2016-03-15

    The area under the receiver operating characteristic (ROC) curve (AUC) is used as a performance metric for quantitative tests. Although multiple biomarkers may be available for diagnostic or screening purposes, diagnostic accuracy is often assessed individually rather than in combination. In this paper, we consider the interesting problem of combining multiple biomarkers for use in a single diagnostic criterion with the goal of improving the diagnostic accuracy above that of an individual biomarker. The diagnostic criterion created from multiple biomarkers is based on the predictive probability of disease, conditional on given multiple biomarker outcomes. If the computed predictive probability exceeds a specified cutoff, the corresponding subject is allocated as 'diseased'. This defines a standard diagnostic criterion that has its own ROC curve, namely, the combined ROC (cROC). The AUC metric for cROC, namely, the combined AUC (cAUC), is used to compare the predictive criterion based on multiple biomarkers to one based on fewer biomarkers. A multivariate random-effects model is proposed for modeling multiple normally distributed dependent scores. Bayesian methods for estimating ROC curves and corresponding (marginal) AUCs are developed when a perfect reference standard is not available. In addition, cAUCs are computed to compare the accuracy of different combinations of biomarkers for diagnosis. The methods are evaluated using simulations and are applied to data for Johne's disease (paratuberculosis) in cattle. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Evaluation of different methods to estimate daily reference evapotranspiration in ungauged basins in Southern Brazil

    Science.gov (United States)

    Ribeiro Fontoura, Jessica; Allasia, Daniel; Herbstrith Froemming, Gabriel; Freitas Ferreira, Pedro; Tassi, Rutineia

    2016-04-01

    Evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance. Due to the higher information requirements of the Penman-Monteith method and the existing data uncertainty, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. This is especially important in Brazil, where the monitoring of meteorological data is precarious. In this study were compared different methods for estimating evapotranspiration for Rio Grande do Sul, the Southernmost State of Brazil, aiming to suggest alternatives to the recommended method (Penman-Monteith-FAO 56) for estimate daily reference evapotranspiration (ETo) when meteorological data is missing or not available. The input dataset included daily and hourly-observed data from conventional and automatic weather stations respectively maintained by the National Weather Institute of Brazil (INMET) from the period of 1 January 2007 to 31 January 2010. Dataset included maximum temperature (Tmax, °C), minimum temperature (Tmin, °C), mean relative humidity (%), wind speed at 2 m height (u2, m s-1), daily solar radiation (Rs, MJ m- 2) and atmospheric pressure (kPa) that were grouped at daily time-step. Was tested the Food and Agriculture Organization of the United Nations (FAO) Penman-Monteith method (PM) at its full form, against PM assuming missing several variables not normally available in Brazil in order to calculate daily reference ETo. Missing variables were estimated as suggested in FAO56 publication or from climatological means. Furthermore, PM was also compared against the following simplified empirical methods: Hargreaves-Samani, Priestley-Taylor, Mccloud, McGuiness-Bordne, Romanenko, Radiation-Temperature, Tanner-Pelton. The statistical analysis indicates that even if just Tmin and Tmax are available, it is better to use PM estimating missing variables from syntetic data than

  13. Evaluation of Method-Specific Extraction Variability for the Measurement of Fatty Acids in a Candidate Infant/Adult Nutritional Formula Reference Material.

    Science.gov (United States)

    Place, Benjamin J

    2017-05-01

    To address community needs, the National Institute of Standards and Technology has developed a candidate Standard Reference Material (SRM) for infant/adult nutritional formula based on milk and whey protein concentrates with isolated soy protein called SRM 1869 Infant/Adult Nutritional Formula. One major component of this candidate SRM is the fatty acid content. In this study, multiple extraction techniques were evaluated to quantify the fatty acids in this new material. Extraction methods that were based on lipid extraction followed by transesterification resulted in lower mass fraction values for all fatty acids than the values measured by methods utilizing in situ transesterification followed by fatty acid methyl ester extraction (ISTE). An ISTE method, based on the identified optimal parameters, was used to determine the fatty acid content of the new infant/adult nutritional formula reference material.

  14. Determination of free acid by standard addition method in potassium thiocyanate

    International Nuclear Information System (INIS)

    Baumann, E.W.

    1982-06-01

    The free acid content of solutions containing hydrolyzable ions has been determined potentiometrically by a standard addition method. Two increments of acid are added to the sample in 1M potassium thiocyanate solution. The sample concentration is calculated by solution of three simultaneous Nernst equations. The method has been demonstrated for solutions containing Al 3+ , Cr 3+ , Fe 3+ , Hg 2+ , Ni 2+ , Th 4+ , or UO 2 2+ with a metal-to-acid ratio of < 2.5. The method is suitable for determination of 10 μmoles acid in 10 mL total volume. The accuracy can be judged from the agreement of the Nernst slopes found in the presence and absence of hydrolyzable ions. The relative standard deviation is < 2.5%. The report includes a survey of experiments with thermometric, pH, and Gran plot titrations in a variety of complexants, from which the method was evolved. Also included is a literature survey of sixty references, a discussion of the basic measurements, and a complete analytical procedure

  15. Standard Test Method for Measuring Fast-Neutron Reaction Rates by Radioactivation of Titanium

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers procedures for measuring reaction rates by the activation reactions 46Ti(n,p) 46Sc + 47Ti(n, np)46Sc. Note 1—Since the cross section for the (n,np) reaction is relatively small for energies less than 12 MeV and is not easily distinguished from that of the (n,p) reaction, this test method will refer to the (n,p) reaction only. 1.2 The reaction is useful for measuring neutrons with energies above approximately 4.4 MeV and for irradiation times up to about 250 days (for longer irradiations, see Practice E 261). 1.3 With suitable techniques, fission-neutron fluence rates above 109 cm–2·s–1 can be determined. However, in the presence of a high thermal-neutron fluence rate, 46Sc depletion should be investigated. 1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E 261. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all...

  16. No-gold-standard evaluation of image-acquisition methods using patient data.

    Science.gov (United States)

    Jha, Abhinav K; Frey, Eric

    2017-02-11

    Several new and improved modalities, scanners, and protocols, together referred to as image-acquisition methods (IAMs), are being developed to provide reliable quantitative imaging. Objective evaluation of these IAMs on the clinically relevant quantitative tasks is highly desirable. Such evaluation is most reliable and clinically decisive when performed with patient data, but that requires the availability of a gold standard, which is often rare. While no-gold-standard (NGS) techniques have been developed to clinically evaluate quantitative imaging methods, these techniques require that each of the patients be scanned using all the IAMs, which is expensive, time consuming, and could lead to increased radiation dose. A more clinically practical scenario is where different set of patients are scanned using different IAMs. We have developed an NGS technique that uses patient data where different patient sets are imaged using different IAMs to compare the different IAMs. The technique posits a linear relationship, characterized by a slope, bias, and noise standard-deviation term, between the true and measured quantitative values. Under the assumption that the true quantitative values have been sampled from a unimodal distribution, a maximum-likelihood procedure was developed that estimates these linear relationship parameters for the different IAMs. Figures of merit can be estimated using these linear relationship parameters to evaluate the IAMs on the basis of accuracy, precision, and overall reliability. The proposed technique has several potential applications such as in protocol optimization, quantifying difference in system performance, and system harmonization using patient data.

  17. Standard Test Method for Effects of Cleaning and Chemical Maintenance Materials on Painted Aircraft Surfaces

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers determination of the effects of cleaning solutions and liquid cleaner concentrates on painted aircraft surfaces (Note 1). Streaking, discoloration, and blistering may be determined visually. Softening is determined with a series of specially prepared pencils wherein determination of the softest pencil to rupture the paint film is made. Note 1—This test method is applicable to any paint film that is exposed to cleaning materials. MIL-PRF-85285 has been selected as a basic example. When other paint finishes are used, refer to the applicable material specification for panel preparation and system curing prior to testing. 1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user ...

  18. Evaluation of the k0 method by its application to (n, γ)RNaa of geological, environmental and clay reference materials

    International Nuclear Information System (INIS)

    Corte, F. de; Lin Xilei; Moens, L.; Wispelaere, A. de; Hoste, J.; Demeter, A.; Simonits, A.

    1984-01-01

    The k 0 standardization method, the state-of-the-art of which is shortly reviewed, has been applied to multi-element reactor neutron activation analysis of (standard) reference materials. The analyses have been performed independently at the Institute for Nuclear Sciences (Gent, Belgium) and the Central Research Institute for Physics (Budapest, Hungary). Results are given for USGS-2 (granite), NBS SRM-1633a (coal fly ash) and FCG (fired clay of Gent). Comparison with literature data shows that the k 0 method, while being experimentally simple, versatile and suited for computerization, offers a potential accuracy of better than 5%. (author)

  19. Performance of NAA methods in an International Interlaboratory Reference Material Characterization Campaign

    International Nuclear Information System (INIS)

    Ihnat, M.

    2000-01-01

    An extensive database of analytical results from a recent biological matrix Reference Material Characterization Campaign permitted an intercomparison of the performances of various methods among each other and with 'true' best estimate concentration values established for these materials. Six different variants of neutron activation analysis (NAA) methods were employed including: instrumental neutron activation analysis, instrumental neutron activation analysis with acid digestion, neutron activation analysis with radiochemical separation, neutron capture prompt gamma activation analysis, epithermal instrumental neutron activation analysis, and neutron activation analysis with preconcentration. The precision and accuracy performance of NAA-based analytical methods are compared with three other major techniques, atomic absorption spectrometry (AAS), atomic emission spectrometry (AES) and mass spectrometry (MS) for 28 elements in 10 natural matrix materials. (author)

  20. The History of Infant Formula: Quality, Safety, and Standard Methods.

    Science.gov (United States)

    Wargo, Wayne F

    2016-01-01

    Food-related laws and regulations have existed since ancient times. Egyptian scrolls prescribed the labeling needed for certain foods. In ancient Athens, beer and wines were inspected for purity and soundness, and the Romans had a well-organized state food control system to protect consumers from fraud or bad produce. In Europe during the Middle Ages, individual countries passed laws concerning the quality and safety of eggs, sausages, cheese, beer, wine, and bread; some of these laws still exist today. But more modern dietary guidelines and food regulations have their origins in the latter half of the 19th century when the first general food laws were adopted and basic food control systems were implemented to monitor compliance. Around this time, science and food chemistry began to provide the tools to determine "purity" of food based primarily on chemical composition and to determine whether it had been adulterated in any way. Since the key chemical components of mammalian milk were first understood, infant formulas have steadily advanced in complexity as manufacturers attempt to close the compositional gap with human breast milk. To verify these compositional innovations and ensure product quality and safety, infant formula has become one of the most regulated foods in the world. The present paper examines the historical development of nutritional alternatives to breastfeeding, focusing on efforts undertaken to ensure the quality and safety from antiquity to present day. The impact of commercial infant formulas on global regulations is addressed, along with the resulting need for harmonized, fit-for-purpose, voluntary consensus standard methods.