scholarly journals Development and metrological characterisation of the new LNE 500 N · m deadweight torque standard machine

ACTA IMEKO ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 168
Author(s):  
C. Duflon ◽  
P. Averlant
Keyword(s):  
Mass Change ◽  
National Metrology Institute ◽  
Comparison Measurements

This paper describes the development and metrological characterisation of the new LNE 500 N · m deadweight torque standard machine. This machine is integrated into the LNE 5 kN · m deadweight torque standard machine. New masses and a mass change platform have been developed and added to the 5 kN · m machine. After this, LNE realised the metrological characterisation of the 500 N · m machine. The determination of the uncertainties of this torque standard machine and the comparison measurements with the LNE 50 N · m deadweight torque standard machine and with CEM, the National Metrology Institute of Spain, are described in this paper. The results show that the estimated uncertainties are satisfactory because they are a factor of about four times smaller than those of the old standard machines.

Molar Absorptivity Values for Aflatoxins and Justification for Their Use as Criteria of Purity of Analytical Standards

1970 ◽  
Vol 53 (1) ◽  
pp. 96-101 ◽  
Author(s):  
J V Rodricks ◽  
L Stoloff ◽  
W A Pons ◽  
J A Robertson ◽  
L A Goldblatt
Keyword(s):  
Thin Layer ◽  
Statistical Study ◽  
Molar Absorptivity ◽  
Confidence Limits ◽  
Components Of Variance ◽  
Significant Difference ◽  
Single Determination ◽  
Comparison Measurements ◽  
Analytical Standards

Abstract Measurements of molar absorptivities in methanol were carried out by two laboratories on samples of anatoxins Bi and Gi prepared and purified independently in four laboratories and on samples of aflatoxins B2 and G2 prepared and purified independently in three laboratories. Molar absorptivities of pure aflatoxins Bi, B2, G1, and G2 in benzene-acetonitrile (98 + 2) were determined at two laboratories. With the exception of aflatoxin G2, no significant difference between aflatoxin samples could be demonstrated. Molar absorptivity values and absorbance ratios for each aflatoxin, based on these data, are given. Statistical 95% confidence limits were established for a single determination of molar absorptivity. A statistical study was made of the components of variance which contribute to the accuracy of the determination of molar absorptivity. A comparison of the fluorescence intensities of spots of various aflatoxin preparations, developed on silica gel-coated thin layer plates, with the amount of aflatoxin in each spotting solution as determined by absorbance measurements, demonstrated the validity of using absorbance and fluorescence comparison measurements for aflatoxin quantitation.

GRACE and GRACE-FO Level-1 V04 Data Processing Status

2020 ◽  
Author(s):  
Christopher Mccullough ◽  
Tamara Bandikova ◽  
William Bertiger ◽  
Carmen Boening ◽  
Sung Byun ◽  
...  
Keyword(s):  
Data Processing ◽  
Attitude Determination ◽  
Precise Orbit Determination ◽  
Mass Change ◽  
Sensor Data ◽  
The Earth ◽  
Analysis Center ◽  
Level 1 ◽  
Gravity Recovery

<p>The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO), launched in May 2018, provides invaluable information about mass change in the Earth system, continuing the legacy of GRACE. Fundamental requirements for successful mass change recovery are precise orbit determination and inter-satellite ranging, determination of the relative clock alignment of the ultra-stable oscillators (USOs), precise attitude determination, and accelerometry. NASA/Caltech Jet Propulsion Laboratory is the official Level-1 data processing and analysis center, and is currently processing software version 04. Here we present analysis of the aforementioned GRACE-FO sensor data, as well a preview of an upcoming GRACE reprocessing, and a discussion of measurement performance.</p>

Development and specification of an accurate cosine-behaviour responsivity radiometer head for infrared temperature radiation

2017 ◽  
Vol 84 (12) ◽  
pp. 769-778
Author(s):  
Richard Dieter Taubert ◽  
Christian Monte ◽  
Christoph Baltruschat ◽  
Marco Schulz ◽  
Jörg Hollandt
Keyword(s):  
Integrating Sphere ◽  
Systematic Determination ◽  
Subsequent Measurement ◽  
Temperature Radiation ◽  
Comparison Measurements

Abstract In the framework of a cooperation between the Physikalisch-Technische Bundesanstalt (PTB) and the European Leading Association of Radiant Gas Heaters Manufacturers (ELVHIS e. V.), an integrating sphere based radiometer head with a cosine-behaviour responsivity was developed. This type of radiometer is applied for the metrological characterization of gas-fired infrared radiant heaters according to the standards DIN EN 416-2 and DIN EN 419-2. A systematic determination of the reflectance/emittance of differently surface texturized plane samples and a subsequent measurement of the angular resolved responsivity of a dedicated manufactured radiometer head prototype series enabled the development of an optimized manufacturing specification in terms of the surface texturizing/electroplating for the integrating sphere. Through comparison measurements employing a second prototype series, manufactured by the PTB and a selected industrial workshop, the manufacturing specification was successfully validated.

scholarly journals Determination of the origin and mass change geochemistry during bauxitization process at the Hangam deposit, SW Iran

2003 ◽  
Vol 37 (5) ◽  
pp. 627-637 ◽  
Author(s):  
S. Liaghat ◽  
M. Hosseini ◽  
A. Zarasvandi
Keyword(s):  
Mass Change ◽  
Sw Iran

Certified Reference Material for Use in 1H, 31P, and 19F Quantitative NMR, Ensuring Traceability to the International System of Units

2017 ◽  
Vol 100 (5) ◽  
pp. 1365-1375 ◽  
Author(s):  
Romana Rigger ◽  
Alexander Rück ◽  
Christine Hellriegel ◽  
Robert Sauermoser ◽  
Fabienne Morf ◽  
...  
Keyword(s):  
High Performance ◽  
Certified Reference Materials ◽  
International System ◽  
National Metrology Institute ◽  
Quantitative Nmr ◽  
Iso Guide 34 ◽  
International System Of Units ◽  
System Of Units ◽  
Application Fields

Abstract In recent years, quantitative NMR (qNMR) spectroscopy has become one of the most important tools for content determination of organic substances and quantitative evaluation of impurities. Using Certified Reference Materials (CRMs) as internal or external standards, the extensively used qNMR method can be applied for purity determination, including unbroken traceability to the International System of Units (SI). The implementation of qNMR toward new application fields, e.g., metabolomics, environmental analysis, and physiological pathway studies, brings along morecomplex molecules and systems, thus making use of 1H qNMR challenging. A smart workaround is possible by the use of other NMR active nuclei, namely 31P and 19F. This article presents the development of three classes of qNMR CRMs based on different NMR active nuclei (1H, 31P, and 19F), and the corresponding approaches to establish traceability to the SI through primary CRMs from the National Institute of Standards and Technology and the National Metrology Institute of Japan. These TraceCERT® qNMR CRMs are produced under ISO/IEC 17025 and ISO Guide 34 using high-performance qNMR.

Improvement in the Sample Mass-Change-Method used for Determination of the Bulk Etch Rate of CR-39 Neutron Detector

2001 ◽  
Vol 40 (Part 1, No. 5A) ◽  
pp. 3474-3475 ◽  
Author(s):  
Null Matiullah ◽  
Iftikhar Ahmad Tahiri ◽  
M. S. Subhani ◽  
Katsuhisa Kudo
Keyword(s):  
Neutron Detector ◽  
Etch Rate ◽  
Mass Change ◽  
Sample Mass ◽  
Bulk Etch Rate

A New Approach for Determination of Cavitation Sensitivity of Water

2003 ◽  
Author(s):  
Winfried Heller
Keyword(s):  
Water Quality ◽  
Tensile Strength ◽  
Standardized Testing ◽  
San Francisco ◽  
Stress Resistance ◽  
Simple Method ◽  
Dynamic Stresses ◽  
Measuring Device ◽  
Comparison Measurements

The conditions for the appearance of cavitation, i.e. the local vaporization of fluid under static or dynamic stresses, are closely connected with the tensile strength of the fluid (Arndt, Keller (1992)). Although the dominant effect of water quality on the cavitation interception has been known for many years (Keller (1981, 1983, 1984)), it is uncommon to measure its stress resistance. A possible reason for that could be the unique stress-resistance probe of Keller (1987, 1994) (Eickmann (1992)), which by itself represents a great engineering break-through, is rather complex and expensive. It has become clear during the ASME/JASME conference in San Francisco, 1999 (Keller, Rott, Striedinger, Awad, Ludwig, Yang, Li), and the Fourth International Symposium on Cavitation in Pasadena 2001 (Keller), that internationally standardized testing conditions are required with respect to water quality (Heller (2000)). A relatively simple method of concurrently measuring tensile strength or cavitation susceptibility in cavitation channels has been developed at the Institute of Fluid Mechanics of the Technische Universita¨t Dresden during the last months. This newly developed tensile strength measuring technique is not only efficient and cheap but can also be installed in any existing cavitation channel with comparably small effort. The presented paper represents the actual developmentstate of the Dresden measuring device. Comparison measurements at the cavitatio n-channels of the Versuchsanstalt Obernach (Dr. Keller), Schiffsbau-Versuchsanstalt Potsdam (Mr. Heinke) and the Schiffsbau-Versuchsanstalt Hamburg (Mr. Friesch) are planed for the following months.

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