Articles (en)

Additive manufacturing at the service of the LNHB

Additive manufacturing (3D printing) technologies have greatly evolved in recent years and are now readily available. Since 2017, the LNHB has been equipped with two 3D printers (manufactured in France by VOLUMIC 3D) in order to take advantage of this technology for various developments in the laboratory.

Additive manufacturing lab at the LNHB


The most important improvement has been the production of support rings for X/γ spectrometry sources; in particular for the SG500 geometry whose positioning has now been greatly improved. The relative standard uncertainty on the SG500 efficiency curve has been reduced from 5% to 1.6% in the energy range from 30 to 2000 keV. The 3D printers now in operation at the LNHB mean that simple supports can be manufactured rapidly, adapted to the various measurement requests for calibration services or within the framework of our research. The delay and cost for the provision of these supports have been significantly reduced. Previously one month was required for a machining service (administrative and manufacturing delay), whereas using our own 3D printing laboratory, this has been reduced to only a few hours, for a cost of a few cents.

A facility for the production of radioactive gas atmospheres

Setting up a facility for the production of radioactive gas atmospheres (H, Kr, Xe, Rn…) for the development and calibration of measurement devices.

A facility for the production of radioactive gas atmospheres for a mixture of isotopes or for a single gas has been designed and is now operational at the LNHB.

It can operate in a pressure range from vacuum to 2 000 hPa, with a temperature range from 18°C to 60°C and a humidity range from 0 to 100% RH. It is possible in this range of conditions to create radioactive gas atmospheres with activities below 1 Bq/m3 up to several MBq/m3, while ensuring the traceability of mixtures using primary standard measurement methods.

The facility was entirely created at the LNHB, which will allow for easy modification and future developments. It can be controlled both manually and also by computer via LabVIEW or Arduino board, which is necessary for the acquisition of the large amount of experimental data. Thanks to this facility, many projects in collaboration with other CEA laboratories, as well as external laboratories, have been started.

Experimental facility for the production of reference atmosphere of radioactive gases (Rn, Xe, Kr, and H isotopes)
B. Sabot, M. Rodrigues, S. Pierre, Applied Radiation and Isotopes 155, 108934 (2020)
https://doi.org/10.1016/j.apradiso.2019.108934

DORN, the French instrument of the Chang’e 6 lunar mission

The lander of China’s Chang’e 6 space mission to the Moon will be equipped with the DORN instrument dedicated to radon measurement. Its launch is scheduled for 2023.
Objectives: to study the outgassing of the regolith but also the transport of this radioactive gas in the Moon’s exosphere with possible extrapolations to other species such as water.

DORN will be realized at the Research Institute of Astrophysics and Planetology IRAP (University of Toulouse III, CNRS, CNES) under the supervision of CNES, in collaboration with CEA (including LNE-LNHB), SUBATECH, Arronax PIG and, abroad, with the support of the Institute of Geology and Geophysics of the Chinese Academy of Sciences, the Beijing University of Geosciences, the Christian-Albrechts University of Kiel and the Planetary Science Institute in the United States.

More information on CNES website.

2019 – International Year of the Periodic Table


The Periodic Table of Chemical Elements is one of the most significant achievements in science, capturing the essence not only of chemistry, but also of physics and biology.

1869 is considered as the year of discovery of the Periodic System by Dmitri Mendeleev. 2019 will be the 150th anniversary of the Periodic Table of Chemical Elements and has therefore been proclaimed the “International Year of the Periodic Table of Chemical Elements (IYPT2019)” by the United Nations General Assembly and UNESCO.

Discover everything about IYPT2019 on https://www.iypt2019.org/

World Metrology Day 2019


World Metrology Day is an annual celebration of the signature of the Metre Convention on 20 May 1875 by representatives of seventeen nations.

Metrology, the science of measurement, plays a central role in scientific discovery and innovation, industrial manufacturing and international trade, in improving the quality of life and in protecting the global environment.

The theme for World Metrology Day 2019 is: The International System of Units – Fundamentally better. This theme was chosen because in November 2018, the General Conference on Weights and Measures agreed one of the largest changes to the International System of Units (the SI) since its inception…
(source BIPM and OIML)

More information on World Metrology Day website.

World Metrology Day 2018


World Metrology Day is an annual celebration of the signature of the Metre Convention on 20 May 1875 by representatives of seventeen nations.

Metrology, the science of measurement, plays a central role in scientific discovery and innovation, industrial manufacturing and international trade, in improving the quality of life and in protecting the global environment.

The theme for World Metrology Day 2018 is Constant evolution of the International System of Units. This theme was chosen because in November 2018, the General Conference on Weights and Measures is expected to agree one of the largest changes to the International System of Units (the SI) since its inception…
(source BIPM and OIML)

More information on World Metrology Day website.

Revision of the SI

At its 25th meeting (November 2014) the CGPM adopted a Resolution on the future revision of the International System of Units. This Resolution built on the CGPM’s previous Resolution (2011), which took note of the CIPM’s intention to propose a revision of the SI and set out a detailed roadmap towards the future changes.

In the revised SI four of the SI base units – namely the kilogram, the ampere, the kelvin and the mole – will be redefined in terms of constants; the new definitions will be based on fixed numerical values of the Planck constant (h), the elementary charge (e), the Boltzmann constant (kB), and the Avogadro constant (NA), respectively. Further, the definitions of all seven base units of the SI will also be uniformly expressed using the explicit-constant formulation, and specific mises en pratique will be drawn up to explain the realization of the definitions of each of the base units in a practical way.
(source BIPM)

More information on the BIPM website.