bluuebunny/crossref_metadata_2025 huggingface dataset:
VLTI/PIONIER survey of disks around post-AGB binaries
Authors: Kluska J. , Van Winckel H. , Hillen M. , Berger J.-P. , Kamath D. , Le Bouquin J.-B. , Min M.
Published: September 2019

Context.Post-asymptotic giant branch (AGB) binaries are surrounded by circumbinary disks of gas and dust that are similar to protoplanetary disks found around young stars.

Aims.We aim to understand the structure of these disks and identify the physical phenomena at play in their very inner regions. We want to understand the disk-binary interaction and to further investigate the comparison with protoplanetary disks.

Methods.We conducted an interferometric snapshot survey of 23 post-AGB binaries in the near-infrared (H-band) using VLTI/PIONIER. We fit the multi-wavelength visibilities and closure phases with purely geometrical models with an increasing complexity (including two point-sources, an azimuthally modulated ring, and an over-resolved flux) in order to retrieve the sizes, temperatures, and flux ratios of the different components.

Results.All sources are resolved and the different components contributing to theH-band flux are dissected. The environment of these targets is very complex: 13/23 targets need models with thirteen or more parameters to fit the data. We find that the inner disk rims follow and extend the size-luminosity relation established for disks around young stars with an offset toward larger sizes. The measured temperature of the near-infrared circumstellar emission of post-AGB binaries is lower (Tsub~ 1200 K) than for young stars, which is probably due to a different dust mineralogy and/or gas density in the dust sublimation region.

Conclusions.The dusty inner rims of the circumbinary disks around post-AGB binaries are ruled by dust sublimation physics. Additionally a significant amount of the circumstellarH-band flux is over-resolved (more than 10% of the non-stellar flux is over-resolved in 14 targets). This hints that a source of unknown origin, either a disk structure or outflow. The amount of over-resolved flux is larger than around young stars. Due to the complexity of these targets, interferometric imaging is a necessary tool to reveal the interacting inner regions in a model-independent way.
Probing planet formation and disk substructures in the inner disk of Herbig Ae stars with CO rovibrational emission
Authors: Bosman Arthur D. , Banzatti Andrea , Bruderer Simon , Tielens Alexander G. G. M. , Blake Geoffrey A. , van Dishoeck Ewine F.
Published: September 2019

Context. CO rovibrational lines are efficient probes of warm molecular gas and can give unique insights into the inner 10 AU of proto-planetary disks, effectively complementing ALMA observations. Recent studies find a relation between the ratio of lines originating from the second and first vibrationally excited state, denoted as v2∕v1, and the Keplerian velocity or emitting radius of CO. Counterintuitively, in disks around Herbig Ae stars the vibrational excitation is low when CO lines come from close to the star, and high when lines only probe gas at large radii (more than 5 AU). The v2∕v1 ratio is also counterintuitively anti-correlated with the near-infrared (NIR) excess, which probes hot and warm dust in the inner disk.

Aims. We aim to find explanations for the observed trends between CO vibrational ratio, emitting radii and NIR excess, and to identify their implications in terms of the physical and chemical structure of inner disks around Herbig stars.

Methods. First, slab model explorations in local thermal equilibrium (LTE) and non-LTE are used to identify the essential parameter space regions that can produce the observed CO emission. Second, we explore a grid of thermo-chemical models using the DALI code, varying gas-to-dust ratio and inner disk radius. Line flux, line ratios, and emitting radii are extracted from the simulated lines in the same way as the observations and directly compared to the data.

Results. Broad CO lines with low vibrational ratios are best explained by a warm (400–1300 K) inner disk surface with gas-to-dust ratios below 1000 (NCO < 1018 cm−2); no CO is detected within or at the inner dust rim, due to dissociation at high temperatures. In contrast, explaining the narrow lines with high vibrational ratios requires an inner cavity of a least 5 AU in both dust and gas, followed by a cool (100–300 K) molecular gas reservoir with gas-to-dust ratios greater than 10 000 (NCO > 1018 cm−2) at the cavity wall. In all cases, the CO gas must be close to thermalization with the dust (Tgas ~ Tdust).

Conclusions. The high gas-to-dust ratios needed to explain high v2∕v1 in narrow CO lines for a subset of group I disks can be naturally interpreted as due to the dust traps that are proposed to explain millimeter dust cavities. The dust trap and the low gas surface density inside the cavity are consistent with the presence of one or more massive planets. The difference between group I disks with low and high NIR excess can be explained by gap opening mechanisms that do or do not create an efficient dust trap, respectively. The broad lines seen in most group II objects indicate a very flat disk in addition to inner disk substructures within 10 AU that can be related to the substructures recently observed with ALMA. We provide simulated ELT-METIS images to directly test these scenarios in the future.
Kinematics around the B335 protostar down to au scales
Authors: Bjerkeli Per , Ramsey Jon P. , Harsono Daniel , Calcutt Hannah , Kristensen Lars E. , van der Wiel Matthijs H. D. , Jørgensen Jes K. , Muller Sébastien , Persson Magnus V.
Published: September 2019

Context. The relationship between outflow launching and the formation of accretion disks around young stellar objects is still not entirely understood, which is why spectrally and spatially resolved observations are needed. Recently, the Atacama Large Millimetre/sub-millimetre Array (ALMA) carried out long-baseline observations towards a handful of young sources, revealing connections between outflows and the inner regions of disks.

Aims. Here we aim to determine the small-scale kinematical and morphological properties of the outflow from the isolated protostar B335 for which no Keplerian disk has, so far, been observed on scales down to 10 au.

Methods. We used ALMA in its longest-baseline configuration to observe emission from CO isotopologues, SiO, SO2, and CH3OH. The proximity of B335 provides a resolution of ~3 au (0.03′′). We also combined our long-baseline data with archival observations to produce a high-fidelity image covering scales up to 700 au (7′′).

Results. 12CO has an X-shaped morphology with arms ~50 au in width that we associate with the walls of an outflow cavity, similar to what is observed on larger scales. Long-baseline continuum emission is confined to <7 au from the protostar, while short-baseline continuum emission follows the 12CO outflow and cavity walls. Methanol is detected within ~30 au of the protostar. SiO is also detected in the vicinity of the protostar, but extended along the outflow.

Conclusions. The 12CO outflow does not show any clear signs of rotation at distances ≳30 au from the protostar. SiO traces the protostellar jet on small scales, but without obvious rotation. CH3OH and SO2 trace a region <16 au in diameter, centred on the continuum peak, which is clearly rotating. Using episodic, high-velocity, 12CO features, we estimate the launching radius of the outflow to be <0.1 au and dynamical timescales of the order of a few years.
Inversion of HIPPARCOS andGaiaphotometric data for asteroids
Authors: Cellino A. , Hestroffer D. , Lu X.-P. , Muinonen K. , Tanga P.
Published: September 2019

Context.Sparse photometric data can be used to determine the spin properties and infer information about the shapes of asteroids. The algorithm adopted for the inversion ofGaiaphotometric data assumes, for the sake of simplicity and to minimize CPU execution time, that the objects have triaxial ellipsoid shapes. In the past, this algorithm was tested against large sets of simulated data and small numbers of sparse photometric measurements obtained by HIPPARCOS.

Aims.After the secondGaiadata release, it is now possible to test the inversion algorithm against small samples of actualGaiadata for the first time. At the same time, we can attempt a new inversion of older HIPPARCOSmeasurements, using an updated version of the photometric inversion algorithm.

Methods.The new version of our inversion algorithm includes the treatment of a Lommel-Seeliger scattering relation especially developed for the case of triaxial ellipsoid shapes. In addition, we also performed inversion attempts using a more refined shape model, based on the so-called cellinoid shapes.

Results.With respect to the old inversion of HIPPARCOSdata carried out in the past, we obtain only marginal improvements. In the case ofGaiadata, however, we obtain very encouraging results. A successful determination of the rotation period is possible in most cases, in spite of the limited time span covered by data published in the secondGaiadata release (GDR2), which makes the determination of the spin axis direction still uncertain. Even a small number of measurements, less than 30 in many cases, are sufficient to obtain a satisfactory inversion solution. Using the more realistic cellinoid shape model, we find further improvement in the determination of the spin period.

Conclusions.This is a relevant validation of GDR2 photometry of asteroids, and proof of the satisfactory performances of the adopted inversion algorithm.
GIARPS High-resolution Observations of T Tauri stars (GHOsT)
Authors: Giannini T. , Nisini B. , Antoniucci S. , Biazzo K. , Alcalá J. , Bacciotti F. , Fedele D. , Frasca A. , Harutyunyan A. , Munari U. , Rigliaco E. , Vitali F.
Published: September 2019

Context. The mechanism for jet formation in the disks of T Tauri stars remains poorly understood. Observational benchmarks to launching models can be provided by tracing the physical properties of the kinematic components of the wind and jet in the inner 100 au of the disk surface.

Aims. In the framework of the GIARPS High-resolution Observations of T Tauri stars (GHOsT) project, we aim to perform a multi-line analysis of the velocity components of the gas in the jet acceleration zone.

Methods. We analyzed the GIARPS-TNG spectra of six objects in the Taurus-Auriga complex (RY Tau, DG Tau, DL Tau, HN Tau, DO Tau, RW Aur A). Thanks to the combined high-spectral resolution (ℜ = 5°0 000−115 000) and wide spectral coverage (~400−2400 nm) we observed several O 0, S +, N 0, N +, and Fe + forbidden lines spanning a large range of excitation and ionization conditions. In four objects (DG Tau, HN Tau, DO Tau, RW Aur A), temperature (Te), electron and total density (ne, nH), and fractional ionization (xe) were derived as a function of velocity through an excitation and ionization model. The abundance of gaseous iron, X(Fe), a probe of the dust content in the jet, was derived in selected velocity channels.

Results. The physical parameters vary smoothly with velocity, suggesting a common origin for the different kinematic components. In DG Tau and HN Tau, Te, xe, and X(Fe) increase with velocity (roughly from 6000 K, 0.05, 10%X(Fe)⊙ to 15 000 K, 0.6, 90%X(Fe)⊙). This trend is in agreement with disk–wind models in which the jet is launched from regions of the disk at different radii. In DO Tau and RW Aur A, we infer xe < 0.1, nH ~ 106−7 cm−3, and X(Fe) ≲ X(Fe)⊙ at all velocities. These findings are tentatively explained by the formation of these jets from dense regions inside the inner, gaseous disk, or as a consequence of their high degree of collimation.
Modeling deuterium chemistry in starless cores: full scrambling versus proton hop
Authors: Sipilä O. , Caselli P. , Harju J.
Published: September 2019

We constructed two new models for deuterium and spin-state chemistry for the purpose of modeling the low-temperature environment prevailing in starless and pre-stellar cores. The fundamental difference between the two models is in the treatment of ion-molecule proton-donation reactions of the form XH+ + Y → X + YH+, which are allowed to proceed either via full scrambling or via direct proton hop, that is, disregarding proton exchange. The choice of the reaction mechanism affects both deuterium and spin-state chemistry, and in this work our main interest is on the effect on deuterated ammonia. We applied the new models to the starless core H-MM1, where several deuterated forms of ammonia have been observed. Our investigation slightly favors the proton hop mechanism over full scrambling because the ammonia D/H ratios are better fit by the former model, although neither model can reproduce the observed NH2D ortho-to-para ratio of 3 (the models predict a value of ~2). Extending the proton hop scenario to hydrogen atom abstraction reactions yields a good agreement for the spin-state abundance ratios, but greatly overestimates the deuterium fractions of ammonia. However, one can find a reasonably good agreement with the observations with this model by increasing the cosmic-ray ionization rate over the commonly adopted value of ~ 10−17 s−1. We also find that the deuterium fractions of several other species, such as H2CO, H2O, and CH3, are sensitive to the adopted proton-donation reaction mechanism. Whether the full scrambling or proton hop mechanism dominates may be dependent on the reacting system, and new laboratory and theoretical studies for various reacting systems are needed to constrain chemical models.
Solar investment risk mitigation − are we all on the same page?
Authors: Sauer Thomas C.
Published: September 2019

Currently, the PV solar sector represents approx. 2% of worldwide annual electricity production (https://webstore.iea.org/world-energy-outlook-2018), and therefore, is just at the verge of becoming visible in most countries. As the PV sector becomes increasingly visible to the next order of magnitude sometime in future, representing 20% in the electricity mix and beyond, it is now a good time to discuss reliability, predictability, and performance of PV power plants and as a consequence, the improvement potential for financial returns. Building on this train of thought, this article will provide a short introduction of PV power plant risks, predominantly related to technical performance. The question of risk mitigation measures will then be discussed: On the one side, quality assurance is a viable risk mitigation measure. However, even with quality assurance measures implemented, there are limitations when it comes to backstopping financial losses in the event that the performance deteriorates more than predicted and warranted by the manufacturers, or if the manufacturers or EPC's are no longer in business when incidental power degrades beyond calculated limits. Insurance solutions seem to provide an additional risk mitigation measure. Most insurance solutions on the market, however, only cover against externally induced risk exposures, e.g. severe weather, theft. Most of these insurance solutions follow a certain minimum standard. A few insurance products offer performance insurances where general cover is less standardized. All this triggers the question of how to look at insurance solutions. The interests of an insurance company are generally different than those of the insured stakeholders. These different viewpoints will be discussed, and selected warranty and insurance aspects will be considered. Recently, approximately 3500 insurance claim cases were statistically analyzed (http://www.pvstatlab.rwth-aachen.de/index.php/PVScan-project.html). Selected results of this analysis will be discussed. The article closes with an outlook of how insurers can likewise mitigate their risk exposure − in the end, insurers are only as good as the balance of the solvency resulting from their business model, or in the terminology of the insurance sector, the loss ratio must be at an acceptable level. This is where IECRE, the IEC System for Certification to Standards Relating to Equipment for Use in Renewable Energy Applications (https://www.iecre.org/), offering an international standard for certification − and in future − a rating system for PV power plants on a system level comes into play.
On the Dispersive Characteristics of Shallow Water Seismic Waves Excited by Air Gun Sound Source in Shallow Water
Authors: Diao Aimin , Cheng Guangli , Wang Zeming
Published: September 2019

In order to study the dispersion characteristics of seabed seismic waves excited by acoustic sources in shallow water, the sound field at liquid-solid interface is derived based on the wave equation firstly, which results demonstrate that the longitudinal wave and transversal wave are not dispersive, while the Scholte wave is normal dispersive. Then, the numerical simulation is carried out on the sound field at the liquid-solid interface excited by the air gun sound source based on high-order staggered grid finite difference method, which results demonstrate that the dispersion phenomenon of Scholte waves is observed and the theoretical analysis results were verified. Finally, the data of experiment in the sea are analyzed based on the transformation, and the dispersion curve of Scholte wave is finely extracted.
Thermo-Elastohydrodynamic Study on Textured Journal Bearing with High-Speed and High-Specific-Pressure
Authors: Wang Lin , Zhang Yu , Chen Guoding
Published: September 2019

The performance of supporting journal bearing of the star gear transmission system in the geared turbo fan engine (GTF) is analyzed. A thermal-elastohydrodynamic analysis model was developed for textured journal bearing used in high-speed and high-specific-pressure conditions. The Navier-Stokes equation, energy equation, and viscosity-temperature equation were calculated by the computational fluid dynamics method. The influence of elastic deformation on bearing thermal hydrodynamic performance was studied in detail. The results indicate that the elastic deformation has an influence on the distribution of oil temperature and oil pressure. Besides, a comparative thermo-elastohydrodynamic analysis was conducted between the textured bearing and the un-textured bearing, and the discrepancies of maximum oil pressure, load carrying capacity and the maximum oil temperature are few. However, the textured bearing has a lower elastic deformation than the un-textured bearing.
Exploring Strong Spinning Formation Mechanisms of GH3030 Superalloy Tapered Rotary Part with Wall Thickness Gradient
Authors: Shu Xuedao , Cen Zewei , Wang Yu , Li Zixuan , Zhu Ying
Published: September 2019

In order to effectively control the deformation of tapered spinning parts with gradually changing wall thickness, the precise forming of such sheet metal casing parts can be realized. This paper uses experiments to establish the true stress-strain curve equations of GH3030 superalloy at normal temperature. Based on the equations, it establishes the finite element model of the strong spinning forming of a GH3030 superalloy tapered rotary part with wall thickness gradient. The equivalent stress field for the strong spinning forming is used to combine the finite element simulation with experiments. The strong spinning forming is simulated, and the distribution characteristics of the equivalent stress field and the equivalent strain field for the strong spinning forming are analyzed in some detail, and their distribution law is obtained. The strong spinning forming mechanisms for the GH3030 superalloy tapered rotary part with wall thickness gradient is clarified. The experimental and simulation results are verified with the conical flange plane degree.
Detailed mechanisms of hydrogen charging and hydrogen stress cracking of steel in liquid ammonia storage
Authors: Crolet Jean-Louis
Published: September 2019

The available polarisation curves of the literature are analysed in view of the theoretical analysis of the corrosive medium in Part I (J.-L. Crolet, Matériaux & Techniques107, 401, 2019) and the new views on passivation and hydrogen charging. The accurate electrochemical conditions of the respective cathodic and “anodic” hydrogen charging are thus defined, or more exactly the paradox of a protonic cathodic reaction only running at high potential. Similarly in the available exposure test results, the locus of the ternary redox equilibrium between ammonia and its two decisive contaminants, oxygen and water, separates contaminated ammonia into two domains, on the one hand, a safe domain where the undersaturated oxygen cannot act as an oxidiser, hence no anodic HSC at the free corrosion potential, and on the other hand, a dangerous domain where oxygen is supersaturated, hence oxidising conditions, steel passivation, high potentials, anodic charging and anodic HSC. Likewise, all the known features of this environmental cracking are also explained, with no exception nor contradiction, including the differences between the liquid and vapour phases. An experimental method is also proposed to directly check the occurrence of anodic charging, and proposals are also made for at the same time improving safety and reducing operational or capital expenditures.
Metallurgical characteristics of refining slag used for high manganese steel
Authors: Yu Huixiang , Yang Dexin , Li Muming , Pan Ming
Published: September 2019

High manganese steel has excellent mechanical properties, which has garnered much attention. Whereas the research on the refining slag used for high Mn steel is very limited. In this study, the metallurgical characteristics of refining slag for high Mn steel were investigated based on thermodynamic calculation with FactSage 6.3 and slag-metal equilibrium reaction in MgO crucible. The calculated liquid zones ofT ≤ 1873 K of CaO-SiO2-Al2O3-8%MgO-5%MnO system are located in the middle region of pseudo-ternary CaO-SiO2-Al2O3. For CaO-SiO2-Al2O3-8%MgO-MnO system, the apparent liquid zone at 1873 K enlarges with MnO content in slag increasing, and moves toward the direction of SiO2and Al2O3content increasing. For CaO-SiO2-Al2O3-MgO-MnO system, the liquidus zone shrinks with the basicity increasing, and moves toward the direction of Al2O3content increasing. The measured MnO content in top slag reacted with high Mn steel was much higher than that reacted with conventional steels. In present experiments, the MnO content was around 5% when CaO-SiO2-Al2O3-MgO slag with basicity of 4 was in equilibrium with high Mn steel (Mn = 10, 20%) at 1873 K. The inclusions in master high Mn steel were mainly MnO type. After reaction with top slag, most inclusions transformed to MnO-SiO2system and MnO-Al2O3-MgO system, in which the MnO content still shared the majority. Thermodynamic calculations show that SiO2in top slag can be reduced by [Mn] in steel to supply [Si] under present experimental condition, which subsequently reacts with [O] in steel bath to form SiO2.
Development of standardized methods for the analysis of amines, terpenes and ammonia in biomethane
Authors: Cuccia Lorena , Sanz Béatrice , Ballestas Castro Dairo , Li Jianrong , van der Veen Adriaan M.H. , Amico di Meane Elena , Moreno Sergi , Culleton Lucy P. , Vorin Djimmy , Senné Célia , Bougueroua Faiza , Pyrée Laurent , Courtois Yann , Tastard Christophe
Published: September 2019

European Commission targets specify that 32% of the European energy consumption should come from renewable sources by 2030. One of the most promising options to reach this target is gas generation from biomass, especially biomethane, for injection into natural gas grid. EN 16723 presents specifications for VOCs, corrosive components and compressor oil in biomethane, impurities monitored because of integrity of gas infrastructure and for health and safety reasons. Currently, it proposes test methods that are neither harmonized nor validated, and usually not dedicated to biomethane. Launched in June 2017, the EMPIR project 16ENG05 Metrology for Biomethane is aimed for specific, robust and standardized analytical methods development, along with novel and improved reference standards. The present paper focusses on the developed methods for the monitoring of amines, terpenes and ammonia involving μGC-TCD, TD-GC-MS and OFCEAS.
Development and metrological characterization of an aerosol generation device dedicated to inhalation toxicology studies: the nanopesticide case
Authors: Hamdaoui Quentin , Gaie-Levrel François , Macé Tatiana , Vaslin-Reimann Sophie , Flamant Frédéric , Bencsik Anna
Published: September 2019

Despite the controversies surrounding the potential health effects associated with engineered nanomaterials, novel agrochemicals combining nanotechnology and pesticides are emerging. These products, named nanopesticides, are being developed to improve the efficiency of conventional agrochemicals. However, they represent an intentional anthropogenic source of nanomaterials within the different environmental compartments which constitutes a possible exposure of agricultural populations notably via the aerosols generated by farming activities. The hazard related to this new type of contaminants must be assessed by using inhalation toxicology studies that are designed to reproduce the complexity of these aerosols exposure, in order to be relevant for human health studies. In the present article, we report an experimental strategy combining both the recommendations in animal experimentation and the OECD guidelines for chemicals testing. To explore the neurotoxicity linked with the chronic exposure to aerosols generated from a nanopesticide, we develop an original device dedicated to inhalation toxicology with rodents. Through this proof of concept study, our cross-disciplinary project aims at proposing a validated methodology to study the inhalation toxicity of complex formulations represented by nanopesticides.
Radius measurement and uncertainty evaluation using three-sphere reciprocity method
Authors: Ho Bing-Lin , Chen Jr-Rung , Kuan Szu-Chi , Hsu Po-Er , Hsieh Tsung-Han , Chen Wen-Jen
Published: September 2019

Three-dimensional (3D) measuring instrument has become widely applied by manufacturers due to the fast measurement capability and the flexible measuring procedure. It is also a crucial topic to evaluate or improve the measuring performance of these instruments, including the contact type like coordinate measuring machines (CMM) or the non-contact type like structure light scanners. Recently, the most commonly used standard feature is a sphere with a non-specular surface. It is because the ceramic materials is used to ensure the durability of the standard spheres, or is limited by the measuring principle of structure light scanners where the measured objects need to be lambertian surface. In the light of these limitations, the interferometry methods could not directly calibrate these standard spheres. In order to calibrate the radius and form of a non-specular sphere, this research focuses on the tactile method of spheres reciprocity method based on the previous researches. More details of the measuring principle and the formulas would be discussed. Final, the uncertainty of this method is evaluated using Monte Carlo method. The evaluated result of uncertainty is less than 10 nm for 15 mm radius sphere. This is very useful for common 3D measuring instrument calibration.
Task‐specific measurement uncertainty budget of Curvic‐coupling using analytical methods
Authors: Gashi Bekim V. , Toman Trevor , Matharu Ranveer S.
Published: September 2019

A number of Industrial reference components manufactured by grinding to achieve tight dimensional tolerances. In this paper, we present an uncertainty budget of a reference forty-tooth #Curvic measured using an accurate Coordinate Measuring Machine (CMM) in a temperature-controlled laboratory. A number of measurements conducted on Curvicto assess measurement repeatability and reproducibility. Expanded uncertainty budget evaluated from twenty-one Influencing factors, giving8.7 µm (7.1 µm from Type A) and 11 µm (9.6 µm from Type A), respectively, for repeatability and reproducibility test (k >2). Measurement uncertainty due to steady-state thermal effects is 2.2 µm. An adaptable model is presented to evaluate transient thermal effects, a factor often neglected in measurement uncertainty. Thermal time constant uncertainty associated with transient thermal effects is evaluated u(τ)= ±398 s, which corresponds to ±15 % of thermal time constant expanded uncertainty, u(τ)= ±2570 s.

#Curvic® (Curvic is a trademark of The Gleason Works, 1000 University Avenue, Rochester, NY, 14603, USA)
Investigation on automated Multiple Decade Ratios precision Divider for Generation of low DC Voltages
Authors: Cerri Roberto , Corona Davide , Galliana Flavio
Published: September 2019

At the National Institute of Metrological Research (INRIM) an automatable precision DC voltage fixed-ratios divider allowing the division ratios of DC Voltages from 10:1 to 107:1. It can be quickly calibrated when necessary and involved in traceability transfer. Its resistors are selected bulk metal foils ones connected in series in four terminal configuration whose values are 90 kΩ, 9 kΩ, 900 Ω, 90 Ω, 9 Ω, 0.9 Ω, 90 mΩ and 10 mΩ. The main advantage of this divider is that it can be automatically calibrated with a calibrator and a digital multimeter. Its calibration starts from a10 V value. It takes advantage of the DMM linearity, in particular in the 10 V range that allows improving its calibration uncertainty. After calibration, it can be used to divide DC Voltages lower than 10 V. Preliminary evaluation of its calibration uncertainties and mid-term stabilities (a week) span respectively from 1.4×10-6 to 6.0×10-4 and from 2.4×10-7 to 4.5×10-4 for ratios from 10:1 to 107:1. This divider could be involved in the calibration of nanovoltmeters in a typical range from 10 V till down to 100 nV.
Measurement setup to characterize electrical standards
Authors: Capra Pier Paolo , Cerri Roberto , Galliana Flavio , Lanzillotti Marco , Pollarolo Alessio , Roccato Paolo
Published: September 2019

At the National Institute of Metrological Research (INRIM) a measuring setup able to vary, accurately and in a selective way, the temperature, humidity and pressure to detect eventual hysteretic phenomena and to evaluate their effects on electrical standards as high precision standard resistors and Zener-diode based DC Voltage standards. Main element of the setup is a pressure-tight case housing the standards and acting the stresses due to the desired parameters. By means of pressure-tight-connectors, the standards under test are connected to the measuring instruments, while the climatic conditions are acquired through inner and external sensors. Humidity is controlled by means of two conditioning containers filled respectively with water and silica-gel, which regulate the air-moisture percentage the case in a range of 10-90%. A pumping system establishes the pressure in the case from 600 hPa to 1400 hPa. The characterization vs. humidity and pressure is made at constant temperature by means of a commercial air-bath acting from 15 and 45 ° C. Preliminary results have been obtained for pressure dependence of commercial 100 Ω resistors and of an INRIM-developed 10 V Zener-diode based DC Voltage standard.
New reference systems for the calibration of HV impulses at LNE
Authors: Saadeddine Hanane , Agazar Mohamed , Fortune Dominique
Published: September 2019

Driven by the need for traceable measurement methods, LNE has developed and characterized new reference measurement systems for the calibration of HV impulses, including lightning impulses (1, 2 µs/ 50 µs) and switching impulses (250 µs/ 2500 µs), according to new requirements of IEC 60060-1 and IEC 60060-2. This paper describes new reference measurement systems, which have been developed and fully characterized at LNE. In addition, the paper describes the test procedure for accurate measurements especially for in-situ calibrations in 5 successive steps; measurements of radiofrequency disturbances, step response of voltage dividers, measurement of the scale factors of voltage dividers, calibration of digitizer’s channels and ranges, measurement of the voltage linearity of the divider under calibration up to maximum voltage.
Choice of parameters for an R&R study and its impact on the measurement capability
Authors: Dubois Christophe , Courtois Peggy
Published: September 2019

When you perform a traditional R&R (Repeatability and Reproducibility), the first practical question that comes to mind is “How many times “n” do we repeat the measurements, and how many operators “p” should we consider?”. As the quality of the standard deviations obtained during this study depends on the parameters n and p, a large number of measurements is required. This is obviously not possible due to environment, time and cost aspects. The question is then, how to optimise the parameters “n” and “p”, for an R&R study? To answer this question, statistics are useful tools, which, combined with your practical skills, will help you to understand the outcome of the study and rationalise your choice.
Capacitance metrology at the BIPM to support National Metrology Institutes
Authors: Moreno J. Angel , Gournay Pierre
Published: September 2019

The Bureau International des Poids et Mesures (BIPM) is an international organization which works to promote and advance a coherent system of measurements throughout the world, traceable to the International System of Units (SI). One of its activities consists of the dissemination of units and the comparison of national measurement standards, which requires the availability of well-known and well-characterized standards. In particular, in the field of electricity, the BIPM supports capacitance measurements based on a quantum reference, impedance bridges and stable transfer standards, establishing traceability to the defining fundamental constants of the SI. In this paper it will be explained how the farad is realized at the BIPM, including a general description of the measuring systems, and how this unit is maintained.
New calibration facility developped at LNE-CETIAT
Authors: Georgin Eric , Bernard Nicolas , Salem Marzougui
Published: September 2019

LNE-CETIAT has developed its own primary realization of the unit in humidity. Willing to have a more versatile generator, the laboratory has developed a new humid air generator based on dilution principle. These facilities are presented in this work as well as the results of two comparisons.
A new EMPIR Project “MetForTC” for Developing Traceable Measurement Capabilities for Monitoring Thermocouple Performance
Authors: Arifovic Narcisa , Sestan Danijel , Zvizdic Davor , Hozic Nedzadeta , Turzo-Andras Emese , Cohodarevic Semir , Strnad Radek , Opel Karsten , Neagu Dimitru , Bordianu Constantin , Spasova Snezana , Vukicevic Tanja
Published: September 2019

In order to enhance the availability of facilities in the field of contact thermometry in European emerging National Metrology Institutes (NMIs) and Designated Institutes (DIs), where access to types of facilities is currently limited an EMPIR Research Potential Project named “Traceable Measurement Capabilities for Monitoring Thermocouple Performance” (MetForTC) has been launched. Overall ten partners has been involved in the project, five of them participating from the emerging countries. This project will develop skills and tools for less experienced NMIs/DIs in order to acquire the required knowledge and expertise in temperature metrology. The MetForTC Project has been addressing the accurate low uncertainty temperature measurements by thermocouple which is of crucial importance for ensuring better manage of the metrological features of the thermal instrumentation used for realizing of temperature measurements as well as to construct a comprehensive approach for the uncertainty budget assessment. Special emphases has been given on novel practical methods and technical capabilities for checking the thermocouple’s drift performance in-situ and easy-to-use thermocouple with integrated miniature cells required to determine the inhomogeneity of thermocouples for primary and secondary calibration laboratory.
Influence of low temperature annealing on Nickel RTDs designed for heat flux sensing
Authors: Mokadem Youssef , Bégot Sylvie , Lanzetta François , Rauch Jean-Yves , Zribi Aymen , Moutarlier Virginie , Barthès Magali
Published: September 2019

In this paper, we study the influence of annealing on the performance of Resistive Temperature Detectors made from Nickel thin films. The aimed application is heat flux sensing. The substrate is made of Borofloat glass with a Chromium adhesive layer. Several annealing temperatures between 150°C and 300°C are applied to this assembly. The thin films as deposited and after annealing are analyzed through SEM images. The evolution of the resistance and the temperature coefficient of the sensor are discussed. An annealing temperature is selected that ensures the repeatability of measurements.
The Contribution of the Metrological Management in the Moroccan Establishments of Blood Donation (Experiment of the regional center of blood transfusion in Oujda Morocco)
Authors: El Bekkaye Khalid , Sidqi Zaina
Published: September 2019

Metrological verification consists of proving by calibration measurements that specified requirements are met. The result of an audit is a compliance decision followed by re-commissioning or non-compliance followed by an adjustment, repair, decommissioning, or device reform. At the regional blood transfusion center of Oujda, from 2010 to 2018 the number of metrological qualification has increased from 88 to 152 acts with compliance going from 92% to 97%, thus the number of visit for preventive and curative maintenance of the share of external companies has also increased since 2010 to 2018 from 10 annual visits to 43 annual visits, which indicates a strong progressive metrological activity and an important place of the metrological process in the continuity of guaranteeing a safety of the result obtained from the operations carried out for the practitioners and for donor and recipient patients of the blood product. An action plan was implemented to correct the anomalies identified such as the acquisition of new metrology equipment, to predict the change of climatic chambers and non-adapted devices, the acquisition of more sophisticated machines and the establishment of a continuous recording system of the cold chain.
Evaluation of Homogeneity in Certified Reference Materials (CRM)
Authors: Dias Florbela A. , Costa Carlos J.
Published: September 2019

The production of Certified Reference Materials (CRM), according to the international standard ISO 17034:2016, has been playing an increasingly role in measurements and accreditation activities of entities/laboratories, with special focus on the field of chemical, biological and clinical tests and physical properties. The IPQ LGR is responsible for the production of various types of CRM, namely gas mixture standards of ethanol in nitrogen (C2H5OH/N2), by gravimetric method according to the international standard ISO 6142-1:2015, and certification by non-dispersive infrared spectroscopy (NDIR) in accordance with ISO 6143:2001. According to ISO 17034:2016, these mixtures have to be evaluated regarding the homogeneity, which is one of the fundamental requirements for the production of CRM. In this communication, the results of the homogeneity study of standards gas mixtures of ethanol in nitrogen are presented, according to a validated measurement procedure, in order to guarantee the traceability to SI units and also to meet the requirements of ISO 17034:2016. The statistical treatment of the data is presented through analysis of variance ANOVA.
Recent progress in chemical measuring capabilities in INM as a result of EMRP/EMPIR Programme
Authors: Buzoianu Mirella , Radu Mihail , Ionescu George Victor
Published: September 2019

New metrology capabilities in chemical area are of great interest as they underpin the traceability of measurement results reported in environment, health or food sectors. To develop such capabilities a consistent research work is needed. Since 2009, the European Metrology Research Program (EMRP) enabled the National Institute of Metrology (INM) from Romania to join several Joint Research Projects (JRPs) in chemical field. Main outcomes of this helped INM in developing and implementing measurement capabilities in gas chromatography (GC) and inductive couple plasma mass spectrometry (ICP-MS). Accordingly, a brief review of the best practice achieved at INM after participating in ENV08 and SIB09 is described. Further, the European Metrology Programme for Innovation and Research (EMPIR) facilitated expanding the existing metrology capabilities/infrastructure within the frame of two research potential projects (RPOT) in chemical field. Aspects regarding developing ICP-MS technique for measuring mass fractions of elements in natural matrix are presented in the frame of EMPIR RPOT1601. Also, some developments are presented in gas chromatography as a result of participating in the EMPIR RPOT1602.
Asymmetric field flow fractionation applied to the nanoparticles characterization: Study of the parameters governing the retention in the channel
Authors: de Carsalade du pont Valentin , Alasonati Enrica , Vaslin-Reimann Sophie , Martin Michel , Hoyos Mauricio , Fisicaro Paola
Published: September 2019

In this work we study the parameters which are often modified to optimize the separation in asymmetrical field flow fractionation, and we observe their impact on the retention behavior of the analyte. The aim of the work is to improve our knowledge of the phenomena which govern the behavior of the analytes in the channel and to have a better understanding of the limits of the actual theoretical model in order to improve it. Results illustrate that the ionic strength influences the effect of the cross flow rate on the retention time of the particle. The question of the determination of the channel thickness was also addressed.
News on the Calibration of Non-Automatic Weighing Instruments
Authors: Medina Nieves
Published: September 2019

EURAMET Calibration Guide No. 18 ‘Guidelines on the Calibration of Non-Automatic Weighing Instruments’ is the document used, not only in Europe but worldwide, as a reference for the calibration of non-automatic weighing instruments. The purpose of the guide is to enhance the equivalence and mutual recognition of calibration results obtained by laboratories performing calibrations of non-automatic weighing instruments. It contains advice on general aspects of calibration, measurement methods and results, including uncertainty of measurement, the calibration certificate and the further use of the instrument. EURAMET’s Calibration Guide No. 18 latest update has been the first one involving direct collaboration with balance manufacturers. In this new version the guide has been improved in many technical details with the aim of clarifying the content of the guide, including some necessary details or simplifying some calculations
Comparison on seismometer sensitivity following ISO 16063-11 standard
Authors: Franck Larsonnier , Guillaume Rouillé , Claire Bartoli , Leonard Klaus , Philipp Begoff
Published: September 2019

Accelerometer calibration by primary and secondary means is now very well covered both in low and medium frequency range. This is obviously not the case for seismometers which are widely used in the world. Up to now, seismometers only have internal checks thanks to an integrated coil. Calibration of these devices address different challenges like large mass and volumes, non-rotatable devices, specific mounting. This inter laboratory comparison will help to investigate these fields and to give feedback to develop a methodology to calibrate seismometers.
Problems of metrological assurance of gas analysis using IR spectroscopy
Authors: Konopelko Leonid , Beloborodov Vitaly , Rumiantsev Dmitry , Chubchenko Ian
Published: September 2019

The survey article presents the results of work on metrological assurance of measurements using IR spectrometers, IR correlation gas analyzers and CRDS instruments. For the successful application of the existing databases in absorption spectroscopy, it is necessary to identify the most accurate data and assign uncertainty to it, based on experimental studies using reference gas mixtures. The properties of the methods that lead to a deterioration in the measurement accuracy were investigated and the ways were suggested to overcome the shortcomings of the measuring methods.
Hands-on activity demonstrating different in-process measurement methods
Authors: Fuehne Joseph
Published: September 2019

Purdue Polytechnic Columbus is one of ten statewide extensions of Purdue University and is located about an hour south of Indianapolis in an economic region dominated by manufacturing. Just less than 40% of the workforce in this 10 county region is directly employed by the manufacturing industry. The primary employer in the region is diesel-engine manufacturer Cummins, Inc. but there are many others including Toyota, Honda, Faurecia, NTN Driveshaft, Valeo, and Aisin. Most of the manufacturing industry is related to automobile production. Purdue Polytechnic Columbus is unique among higher education institutions due to a partnership with diesel-engine manufacturer Cummins Inc. that has led to an environmentally-controlled metrology lab located within the university facility. This puts Purdue Polytechnic Columbus in a unique position to develop and offer training and education programs targeted to local industry and local education institutions. There have been many recent reports of shortages of trained metrology personnel. As a university, Purdue Polytechnic Columbus has developed many programs to engage young people in the STEM disciplines to foster interest in manufacturing and engineering careers. This work attempts to develop a hands-on activity that emphasizes the importance of measurement within the broader context of assembly-line manufacturing. Participants create multiple assembly lines to produce a simple fixture, utilizing various measurement tools to increase quality and improve efficiency. The last effort employs go/no-go gauges to illustrate the value of those tools in manufacturing to improve quality and efficiency.
Les processus de contestation dans le cadre des candidatures des villes européennes aux Jeux olympiques et paralympiques 2024
Authors: Bourbillères Hugo , Koebel Michel
Published: September 2019

Pour un pays ou une métropole, être candidat à l’accueil des Jeux olympiques et paralympiques (JOP) est un enjeu de taille. Pendant longtemps, cela constituait une décision et un engagement diplomatiques et restait confiné dans le secret de milieux politiques et économiques n’appelant pas au débat public. L’actualité récente a fait entrer en jeu de nouveaux acteurs dans le processus, et notamment le citoyen. Ce sont ces changements dans les rapports entretenus entre les candidats aux JOP et les citoyens qui sont l’objet de la présente recherche. Cette contribution présente les résultats exploratoires d’un projet IdEx « post-doctorat » (2018–2020). Après avoir présenté une recension des écrits portant sur les impacts des grands événements sportifs internationaux (GESI) et discuté la question de la contestation et de la défiance de l’opinion publique à l’égard de l’accueil des JOP, nous reviendrons, à partir d’une analyse documentaire, sur les différents cas des candidatures de villes européennes aux JOP 2024. Paris (France) fut déclaré vainqueur, sans référendum, mais aussi finalement sans plus aucun rival ; Rome (Italie) a retiré sa candidature suite au changement de maire et de politique municipale ; Hambourg (Allemagne) a organisé un référendum et a vu le « non » l’emporter de peu ; et Budapest (Hongrie) a retiré sa candidature sur des arguments économiques, mais suite à une pétition d’origine étudiante (mouvementMomentum).