Despite the ready availability and use of nanomechanical testequipment, emerging materials test standards and the existenceof nanoscale length metrology, no artefacts, standard referencematerials, or calibrated force cells are readily available fromany NMI for the calibration of the small forces encountered innanomechanical testing, though as described above, effortsto develop such devices are underway. As these largelyindependent efforts by the world’s NMIs begin to coalescethrough activities within various standards organizations, wethink it prudent for the potential users of such standardsto be informed of the emerging hierarchy. Our goal asa national metrology institute is to encourage a system ofsmall force metrology, complete with primary standards,redundant cross checks and transfer artefacts that can place themeasurement of small forces—so central to nanomechanicaltesting—on a ﬁrm metrological basis. The success of suchan endeavour depends on timely communication within adiverse group that includes instrument manufacturers andusers, materials scientists and process engineers, standardslaboratories and industrial metrologists and national metrologyinstitutes around the globe. It is vital that all parties with astake in this problem be aware of the emerging solutions, andthat they have the opportunity to offer their perspective. Wehope this paper will serve as an effective reference to catalysethe use of quantitative methods for the evaluation of materials,processes and devices in terms of traceably measured forcesand displacements.
the three-state folding of a single protein molecule