Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI mass unit, the kilogram. Creating the optimum vacuum environment for mass metrology requires careful design and selection of construction materials, plumbing components, pumping, and pressure gauging technologies. We review the vacuum technology(1) required for mass metrology and suggest procedures and hardware for successful and reproducible operation.
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http://dx.doi.org/10.6028/jres.116.014 | DOI Listing |
Anal Bioanal Chem
January 2025
Turkish Petroleum Refineries Co. TÜPRAŞ R&D Center, Körfez, Kocaeli, 41790, Türkiye.
Monoelemental calibration solutions are the most common reference in elemental analysis, linking measurement results to the International System of Units (SI). National Metrology Institutes (NMI) prepare these solutions as certified reference materials (CRM) and determine their elemental mass fraction with high accuracy. Characterization with high accuracy is one of the most critical steps in CRM production.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
Guangdong Subcenter of the National Center for Soybean Improvement, College of Agriculture, South China Agricultural University, Guangzhou 510642, China.
As complex quantitative traits, soybean seed oil and protein contents are governed by dynamic proteome networks that remain largely unknown. Here, we investigated the dynamic changes of the proteome during seed maturation across two soybean varieties with contrasting seed oil and protein content. Through optimizing the detectability of low-abundance proteins and utilizing library-free data-independent acquisition (directDIA) mass spectrometry, we unprecedentedly identified 7414 proteins and 3975 protein groups (PGs), substantially expanding the soybean seed proteome.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Division of Chemical and Material Metrology, Korea Research Institute of Standards and Science (KRISS), Daejeon, 34133, Republic of Korea.
Ruthenium (Ru)-based electrocatalysts have shown promise for anion exchange membrane water electrolysis (AEMWE) due to their ability to facilitate water dissociation in the hydrogen evolution reaction (HER). However, their performance is limited by strong hydrogen binding, which hinders hydrogen desorption and water re-adsorption. This study reports the development of RuNi nanoalloys supported on MoO, which optimize the hydrogen binding strength at Ru sites through modulation by adjacent Ni atoms.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Department No. 78 Physical and Technical Problems of Metrology, National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow, Russia.
Monodisperse films of spherical tantalum oxide (V) nanoclusters and spherical tantalum nanoclusters with a tantalum oxide shell with diameters of 1.4-8 nm were obtained by magnetron sputtering. The size of the deposited nanoclusters was controlled using a quadrupole mass filter.
View Article and Find Full Text PDFClin Chem Lab Med
January 2025
70777 TUBITAK National Metrology Institute (TUBITAK UME), Kocaeli, Türkiye.
Objectives: An analytical protocol based on isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS), which includes a peptide-based calibration strategy, was developed and validated for the determination of cardiac troponin I (cTnI) levels in clinical samples. Additionally, the developed method was compared with a protein-based calibration strategy, using cTnI serving as a model for low-abundant proteins. The aim is to evaluate new approaches for protein quantification in complex matrices, supporting the metrology community in implementing new methods and developing fit-for-purpose SI- traceable peptide or protein primary calibrators.
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