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Organisationseinheit der BAM
TrainMiC® is a European programme for lifelong learning on how to interpret the metrological requirements in chemistry. It is operational across many parts of Europe via national teams. These teams use shareware pedagogic tools which have been harmonised at European level through the joint effort of many experts across Europe working as an editorial board. The material has been translated into 14 different languages. This report includes four TrainMiC® presentations: 1. Uncertainty of measurement — Part I Principles; 2. Uncertainty of measurement — Part II Approaches to evaluation; 3. Statistics for analytical chemistry — Part I; and 4. Statistics for analytical chemistry — Part II
Supplementary comparison study - measurement capabilities for the quantification of ethanol in water
(2022)
The accurate quantification of ethanol in water is essential for forensic applications such as blood and breath alcohol testing and for commercial applications such as the assessment of alcoholic beverages.
The intercomparison EURAMET.QM-S14 is part of a capacity building project named ALCOREF “Certified forensic alcohol reference materials”
that is running within the European Metrology Programme for Innovation and Research (EMPIR). The intercomparison should allow project partners and other interested National Metrology Institutes (NMIs) and Designated Institutes (DIs) to benchmark their analytical methods for the quantification of ethanol in water. The study plan was agreed by the European Association of National Metrology Institutes (EURAMET) Subcommittee Bio- and Organic Analysis (SCBOA) and the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) in February and April 2019, respectively. The intercomparison was coordinated by BAM. Two concentration levels relevant for the calibration and verification of evidential breath alcohol analysers were distributed to study participants. Fifteen institutes from 15 countries registered for the intercomparison and returned results. Participants mostly applied gas chromatography with flame ionisation detection (GC-FID) or mass spectroscopy (GC-MS), one participant used titrimetry and one participant employed a test bench for breath analyser calibration (“bubble train”). Participants did either in-house purity assessment of their commercial ethanol calibrants by Karl-Fischer titration, chromatographic methods, quantitative nuclear magnetic resonance spectroscopy (qNMR) and/or density measurements; or they used ethanol/water Certified Reference Materials (CRMs) from NMIs/DIs for calibration.
CCQM OAWG agreed to use a consensus value from participants results that utilizes the reported uncertainties as Key Comparison Reference Value (KCRV). The Gaussian Random effects model with Hierarchical Bayesian solution (HB-REM) is a reasonable approach in this case. The KCRVs and Degrees of Equivalence (DoEs) were calculated with the NIST consensus builder version 1.2 Hierarchical Bayes procedure.
Successful participation in the interlaboratory comparison has demonstrated the capabilities in determining the mass fraction of ethanol in aqueous matrices in the range 0.1 mg/g to 8 mg/g. Fourteen out of 15 participants have successfully quantified both samples, one participant successfully quantified only the lower-level (0.6 mg/g) sample.
Overview of different strengthening techniques applied on walls used in historical structures
(2012)
Segregation to grain boundaries affects their cohesion, corrosion, and embrittlement and plays a critical role in heterogeneous nucleation. In order to quantitatively study segregation and low-dimensional phase separation at grain boundaries, here, we apply a density-based phase-field model. The current model describes the grain-boundary thermodynamic properties based on available bulk thermodynamic data, while the grain-boundary-density profile is obtained using atomistic simulations. To benchmark the performance of the model, Mn grain-boundary segregation in the Fe–Mn system is studied. 3D simulation results are compared against atom probe tomography measurements conducted for three alloy compositions. We show that a continuous increase in the alloy composition results in a discontinuous jump in the segregation isotherm. The jump corresponds to a spinodal Phase separation at grain boundary. For alloy compositions above the jump, we reveal an interfacial transient spinodal phase separation.
The transient spinodal phenomenon opens opportunities for knowledge-based microstructure design through the chemical manipulation of grain boundaries. The proposed density-based model provides a powerful tool to study thermodynamics and kinetics of segregation and phase changes at grain boundaries.
Among the strategies to produce healable thermosetting systems is their modification by the addition of thermoplastic particles. This work investigates the influence of poly(ethylene-co-methacrylic acid) (EMAA) on fibermatrix interfacial properties of a glass fiber reinforced epoxy matrix composite. Epoxy-EMAA interactions were evaluated using differential scanning calorimetry (DSC) and infrared spectroscopy. The effects of EMAA on the epoxy network formation were evidenced by changes in glass transition temperature, cure kinetics and alteration of chemical groups during cure. Interfacial shear strength (IFSS) measurements obtained by single fiber pull-out tests indicate similar interfacial properties for pure and EMAA modified epoxy. Additionally, the potential for self-healing ability of an EMAA modified epoxy was demonstrated. However, IFSS after a healing cycle for the EMAA modified epoxy was lower as compared to the pure epoxy, because of the lower fiber-EMAA interfacial shear strength. So, thermoplastic healing agents has not only to fill cracks in the matrix material, but also have to be optimized regarding its interface properties to the reinforcing fibers.
The aim of this work is to evaluate the feasibility of the direct radiography on weld
inspection in oil pipelines and gas pipeline during the manufacturing process. To that, 6 specimens
with 6 different thickness and varied height of reinforced weld with 5 different kinds of defects
were made. All samples were radiographied using Class I films and flat panel. For all specimens the
inspection length was 8''. Thus, with the flat panel the detector-to-object distance varied so that it
may adequate to several diameters of the tubes.
The detector-to-object distance was calculated based on the physical size of the detector
taking into consideration a safe distance between the tube curvature and the flat panel extremities,
keeping the lowest possible magnification factor so that it could be obtained the length of the
inspection. Images with 6 integration time for each experimental arrangement were obtained.
The images obtained with the Flat Panel/YXLON system were analyzed according to their
quality by using the Contrast parameters (essential wire) (DNV 2007/ IS0 12096 with
reinforcement and ISO 10893-7 basis material), Basic Spatial Resolution BSR (ISO 10893-7)
and normalized signal-to-noise ratio - SNRN (ISO 10893-7) and by detectability using as reference
the conventional radiography.
The results showed that for all thickness, the exposure time used to meet the image quality
requirements were below with direct radiography. However the BSR were not reached for thickness
of 4.85, 6.40 and 9.67 mm, therefore the compensation principle established by ISO 10893-7 was
considered, that is, one more contrast wire for a less wire pair.
The digital technique proved to be more sensitive to real defects found on welds than the
conventional technique. Then it can be conclude that the digital radiography utilizing the flat panel
can be applicable to the oil and gas segment with advantages over conventional technique as to
quality aspects, productivity, environment, safety and health.