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Liste der bei der PTB angezeigten und geprüften Schusswaffen gemäß § 9 Abs. 2 Nr. 1 Beschussgesetz (BeschG)
No full textListe der bei der PTB angezeigten und geprüften Schusswaffen gemäß § 9 Abs. 2 Nr. 1 Beschussgesetz (BeschG
Technische Kompetenzbereiche für Vergleichsmessungen : Richtlinie DKD-R 0-1
No full textDas Ziel dieser Richtlinie ist die Definition von technischen Kompetenzbereichen (auf der Grundlage des Dokuments EA-4/18 G:2021 Guidance on the level and frequency of proficiency testing participation) und Verfahren für die Sicherung der Validität von Ergebnissen von Kalibrierlaboratorien im Zusammenhang mit ihrer Akkreditierung. Diese Definitionen stellen die Mindestanforderungen an den Umfang und die Zeitintervalle für entsprechende Kompetenznachweise dar und können auf der Basis risikobasierter Ansätze sachgerecht modifiziert werden (ILAC-P9:01/2024 ILAC Policy for Proficiency Testing and/or Interlaboratory comparisons other than Proficiency Testing). Im Regelfall erfolgt die Sicherung der Validität von Ergebnissen gemäß DIN EN ISO/IEC 17025:2018 Kap. 7.7 durch regelmäßige Vergleichsmessungen mit Laboratorien gleicher bzw. höherer Kompetenz oder durch erfolgreiche Teilnahme an verfügbaren Eignungsprüfungen (EP). In Fällen, in denen sinnvolle Vergleiche bzw. EP nicht möglich oder verfügbar sind müssen andere Überprüfungsmethoden der technischen Kompetenz in diesen Bereichen vereinbart werden. Gleichwertige Regelungen sollten angewendet werden für die Bewertung von Anbietern von EP (DIN EN ISO/IEC 17043: 2023, DIN ISO 13528:2020) für Kalibrierlaboratorien
Ringvergleich Strömungsgeschwindigkeit im Bereich von 1 m/s bis 35 m/s mittels Flügelrad-Anemometer : Vergleichsbericht DKD-V 11-4
No full textDer in diesem Bericht zusammengefasste Ringvergleich soll der Überprüfung der Vergleichbarkeit der Kalibrierergebnisse der teilnehmenden Kalibrierlaboratorien im Sinne von Punkt 7.7.2 der DIN EN ISO/IEC 17025:2018 als Eignungsprüfung dienen. Der Ringvergleich wurde von den Mitgliedern des DKD-Fachausschusses Strömungsmessgrößen für die Messgröße Strömungsgeschwindigkeit durchgeführt. Als Transfernormal diente ein charakterisiertes Flügelradanemometer. Die Messungen wurden von Januar bis November 2020 durchgeführt. Für die Leistungsbeurteilung der Teilnehmer wurde, wie bei Kalibrierungen üblich, die standardisierte Leistungskenngröße En verwendet (beschrieben in DIN EN ISO/IEC 17043:2023 und DIN ISO 13528:2020). Grundlage dieses Bewertungsansatzes ist der Vergleich der Differenz des Ergebnisses des Teilnehmers mit einem zugewiesenen Referenzwert. Dabei wird sowohl die angegebene Unsicherheit des Teilnehmers als auch die Unsicherheit des zugewiesenen Werts berücksichtigt. Im unteren Geschwindigkeitsbereich (1 m/s, …, 5 m/s) stimmen die Ergebnisse alle Teilnehmer gut überein. Im Geschwindigkeitsbereich von 10 m/s, …, 35 m/s ist eine zunehmende Streuung der Messwerte zu erkennen, was sich in der Vergleichbarkeit der Ergebnisse der Teilnehmer untereinander sowie in den En-Werten niederschlägt. Zu steigenden Geschwindigkeiten hin bilden sich zwei „Äste“ mit Gruppen von Messergebnissen aus – einer, der zunehmend in Richtung negativer Abweichungen tendiert, und einer, der im Bereich positiver Abweichungen liegt. Von 71 Messwerten führten 65 zu konsistenten Datensätzen und flossen in die Berechnung der Referenzwerte ein. Dies entspricht einer Quote von 91,5 %. Für 10 Messergebnisse konnte |En| < 1 nicht erfüllt werden. Dies entspricht 14,1 % aller Messwerte und ist deutlich zu hoch. Aufgrund der statistischen Verteilung im Zusammenhang mit dem Erweiterungsfaktor k = 2 liegt der Erwartungswert bei lediglich 5 %
Determination and specification of the smallest achievable measurement uncertainties in the calibration of electronic non-automatic weighing instruments : Expert report DKD-E 7-4
No full textILAC and BIPM agreed to replace the term ‘Best Measurement Capability’ (BMC) previously used within the scope of accreditation of calibration laboratories by the term ‘Calibration and Measurement Capability’ (CMC) from Appendix C of the Mutual Recognition Arrangement of the International Committee for Weights and Measures (CIPM MRA). The aim of this expert report is to provide accredited calibration laboratories with detailed information in order to help them determine and evaluate the best calibration and measurement capabilities and the smallest achievable measurement uncertainties when calibrating non-automatic weighing instruments. The CMC to be determined must describe the measurement uncertainty for the best available weighing instrument. It must be possible to calibrate this weighing instrument in such a way that the stated CMC is demonstrably achieved. Particular attention is paid to the term ‘best available weighing instrument’. In addition, this report outlines the specifications and assumptions that apply in order to determine the necessary measurement uncertainty contributions. Finally, a uniform, rule-compliant presentation of CMC data (calibration and measurement capabilities) in accordance with ILAC-P14 and ILAC-G18 (e.g. in the appendices to the accreditation certificates) should be derived. This revised presentation can serve as a basis for future accreditations in the field of calibration of non-automatic weighing instruments, as well as for the presentation of the measurement uncertainty associated with an actual measured value, as specified in calibration certificates
Measurement data for the hyperfine splitting and the lifetime of the ²F_⁷⁄₂ clock state in ¹⁷³Yb⁺
No full textThis file includes the measurement data that supports our finding for the paper “Nuclear spin quenching of the ²1/2→²7/2 electric octupole transition in ¹⁷³Yb⁺”, DOI https://doi.org/10.1103/fx1b-5666.
The finding includes the measured frequencies and hyperfine splittings of the ²1/2→²7/2 electric octupole transition in ¹⁷³Yb⁺.
In addition, the Rabi frequencies of several clock transitions are measured, that is related to the strength of the hyperfine induced electric dipole decay channel, which is caused by the large nuclear deformation of ¹⁷³Yb⁺ and its nuclear spin of I=5/2.description of the individual folders:
- Frequency_data: includes the data for the absolute frequency and hyperfine splittings.
- Coh_excitation: includes experimental data (txt file), analysis script (python) and the result plots (png) for transitions interrogated with coherent excitation.
- RAP: includes experimental data (txt file), analysis script (python) and the result plots (png) for transitions interrogated with rapid adiabatic passage technique.
- Summary: includes a ppt-file to summarize the result from three measurement compaigns, for each measurement campaign, the calculation of the determined hyperfine splitting can be found in the corresponding Excel file.
- Multi_ion_spectrum: includes the experimental data (txt file) and the plotting script (python) to regenerate fig. 3 in the manuscript.
- Transition_rate: includes the data for the measured Rabi frequency ratios
- 1_low_nbar: includes measurement data (txt file) and analysis script (python script) for the measured Rabi pi time under well controlled condition. Also the plotting script for Fig.1 in the manuscript can be found here.
- 2_high_nbar: includes measurement data (txt file) and analysis script (python script) for the measured Rabi pi time at increased ion temperature.
- 3_Additional_measurements: includes the measurement data (txt file) and analysis script (python script) mentioned in the End Matter of the manuscript.
- Summary.xlsx: a Microsoft Excel file that summarizes the analyzed Rabi pi time, to reproduce Table II in the manuscript.This project has been supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through grant CRC SFB 1227 (DQ-mat, project B03) and through Germany\u27s Excellence Strategy EXC-2123 QuantumFrontiers - 390837967.
We acknowledge support by the project 22IEM01 TOCK, which has received funding from the EMPIR programme co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation programme.
This work is also supported by Funding support from the NSRF via the Program Management Unit for Human Resources \& Institutional Development, Research and Innovation [grant number B39G680007] and by the Max-Planck-RIKEN-PTB-Center
Liste der bei der PTB angezeigten und geprüften Schusswaffen gemäß § 9 Abs. 2 Nr. 1 Beschussgesetz (BeschG)
No full textListe der bei der PTB angezeigten und geprüften Schusswaffen gemäß § 9 Abs. 2 Nr. 1 Beschussgesetz (BeschG
Harmonisation of methane isotope ratio measurements from different laboratories using atmospheric samples
No full textEstablishing interlaboratory compatibility among measurements of stable isotope ratios of atmospheric methane (δ 13C-CH₄ and δD-CH4) is challenging. Significant offsets are common because laboratories have different ties to the VPDB or SMOW-SLAP scales. Umezawa et al. (2018) surveyed numerous comparison efforts for CH₄ isotope measurements conducted from 2003 to 2017 and found scale offsets of up to 0.5 ‰ for δ¹³C-CH₄ and 13 ‰ for δD-CH₄ between laboratories. This exceeds the World Meteorological Organisation Global Atmospheric Watch (WMO-GAW) network compatibility targets of 0.02 ‰ and 1 ‰ considerably. We employ a method to establish scale offsets between laboratories using their reported CH4 isotope measurements on atmospheric samples. Our study includes data from eight laboratories with experience in high-precision isotope ratio mass spectrometry (IRMS) measurements for atmospheric CH₄. The analysis relies exclusively on routine atmospheric measurements conducted by these laboratories at high-latitude stations in the Northern and Southern Hemispheres, where we assume each measurement represents sufficiently well-mixed air at the latitude for direct comparison. We use two methodologies for interlaboratory comparisons: (I) assessing differences between time-adjacent observation data and (II) smoothing the observed data using polynomial and harmonic functions before comparison. The results of both methods are consistent, and with a few exceptions, the overall average offsets between laboratories align well with those reported by Umezawa et al. (2018). This indicates that interlaboratory offsets remain robust over multi-year periods. The evaluation of routine measurements allows us to calculate the interlaboratory offsets from hundreds, in some cases thousands of measurements. Therefore, the uncertainty in the mean interlaboratory offset is not limited by the analytical error of a single analysis but by real atmospheric variability between the sampling dates and stations. Using the same method, we assess this uncertainty by investigating measurements from four high-latitude sites analysed by the INSTAAR laboratory. After applying the derived interlaboratory offsets, we present a harmonised time series for δ¹³C-CH₄ and δD-CH₄ at high northern and southern latitudes, covering the period from 1988 to 2023
D5: Good practice guide for the analysis of CH₄ source gases for δ13C(CH4) and δ2H(CH4) (part1) or Δ13CH3D and Δ12CH2D2 (part 2) by OIRS and IRMS, including sample handling, purification, optimised analytical procedures and traceability to the international standards and target uncertainties δ13C(CH4): 0.2 ‰, δ2H(CH4): 2 ‰, Δ13CH3D: 0.5 ‰, Δ12CH2D2: 2 ‰.
No full textGood practice guide for the analysis of CH4 source gases for δ13C(CH4) and δ2H(CH4) (part1) or Δ13CH3D and Δ12CH2D2 (part 2) by OIRS and IRMS, including sample handling, purification, optimised analytical procedures and traceability to the international standards and target uncertainties δ13C(CH4): 0.2 ‰, δ2H(CH4): 2 ‰, Δ13CH3D: 0.5 ‰, Δ12CH2D2: 2 ‰
D3: Report describing the development of measurement methods for isotope ratios that are traceable to the SI and summarising the advantages/disadvantages of applying them to more commonly available techniques by providing suitable operation procedures focusing on stable polluting elements
No full textThe objective of WP2 – Advancing stable and long-lived radiogenic isotope ratio measurements of environmental pollutants was to develop robust and broadly applicable methods for the determination of isotope ratios of stable and long-lived radionuclides by mass spectrometry. The target performance was to achieve measurement uncertainties sufficiently low to resolve natural mass-dependent isotope fractionation. For the development and optimisation of these methods, the environmentally relevant elements Li, B, Cr, Cd, Ni, Sb, Pb, and U were selected as key indicators.
This report presents the state of the art and the methodological improvements achieved within the MetroPOEM project. The work focused on isotope ratio determination using a range of mass spectrometric techniques and includes i) a systematic comparison of accuracy and precision across different instrument platforms; ii) the development and optimisation of both manual and automated chemical separation procedures; and iii) the implementation of collision/reaction cell technologies to resolve spectral interferences
PriSpecTemp report: literature study on experimental line intensity of CO, CO2 and O2
No full textThis report is an overview of the existing literature sources for the atmospheric “sensor" molecules (CO, CO2, O2). Existing accurate measurements of the line intensity in different frequency ranges (molecular bands), suitable for both highly accurate ab initio calculations, measurements, and specification of the reference temperatures are targeted. The document is partitioned as follows: after a brief introduction in the second section, 3rd, 4th and 5th sections are dedicated to carbon monoxide, carbon dioxide and molecular oxygen, respectively