TY - JOUR A1 - Hackley, V.A. A1 - Patton, J. A1 - Lum, L.-S. H. A1 - Wäsche, Rolf A1 - Naito, M. A1 - Abe, H. A1 - Hotta, Y. A1 - Pendse, H. T1 - Analysis of the isoelectric point in moderately concentrated Alumina suspensions using electroacoustic and streaming potential methods PY - 2002 SN - 0193-2691 SN - 1532-2351 VL - 23 IS - 5 SP - 601 EP - 617 PB - Dekker CY - New York, NY AN - OPUS4-2080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wäsche, Rolf A1 - Naito, M. A1 - Hackley, V.A. T1 - Experimental study on zeta potential and streaming potential of advanced ceramic powders N2 - Zeta potential as measured with the electrokinetic sonic amplitude (ESA) method has been compared to streaming potential as measured with the particle charge detection (PCD) method. The measurements have been carried out on identical suspensions of a-Al2O3, SiC and Si3N4 with a solids volume fraction of 1% and 10%. Zeta potential and streaming potential are related by a linear function. The correlation coefficients for this relationship are better than 0.99 for the suspensions with 1% solids loading. For the suspensions with 10% solids loading, correlation coefficients are slightly lower due to the influence of increasing viscosity. Regardless of lower correlation at the higher solids loading, the isoelectric pH is constant within the limits of accuracy of the pH measurements. KW - Zeta potential KW - Streaming potential KW - Ceramic powders KW - Correlation of measurement PY - 2002 DO - https://doi.org/10.1016/S0032-5910(01)00462-4 SN - 0032-5910 SN - 1873-328X VL - 123 SP - 275 EP - 281 PB - Elsevier CY - Amsterdam AN - OPUS4-1430 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stefaniak, A.B. A1 - Hackley, V.A. A1 - Roebben, G. A1 - Ehara, K. A1 - Hankin, S. A1 - Postek, M.T. A1 - Lynch, I. A1 - Fu, W.-E. A1 - Linsinger, T.P.J. A1 - Thünemann, Andreas T1 - Nanoscale reference materials for environmental, health and safety measurements: needs, gaps and opportunities N2 - The authors critically reviewed published lists of nano-objects and their physico-chemical properties deemed important for risk assessment and discussed metrological challenges associated with the development of nanoscale reference materials (RMs). Five lists were identified that contained 25 (classes of) nano-objects; only four (gold, silicon dioxide, silver, titanium dioxide) appeared on all lists. Twenty-three properties were identified for characterisation; only (specific) surface area appeared on all lists. The key themes that emerged from this review were: 1) various groups have prioritised nano-objects for development as 'candidate RMs' with limited consensus; 2) a lack of harmonised terminology hinders accurate description of many nano-object properties; 3) many properties identified for characterisation are ill-defined or qualitative and hence are not metrologically traceable; 4) standardised protocols are critically needed for characterisation of nano-objects as delivered in relevant media and as administered to toxicological models; 5) the measurement processes being used to characterise a nano-object must be understood because instruments may measure a given sample in a different way; 6) appropriate RMs should be used for both accurate instrument calibration and for more general testing purposes (e.g., protocol validation); 7) there is a need to clarify that where RMs are not available, if '(representative) test materials' that lack reference or certified values may be useful for toxicology testing and 8) there is a need for consensus building within the nanotechnology and environmental, health and safety communities to prioritise RM needs and better define the required properties and (physical or chemical) forms of the candidate materials. KW - Engineered nanomaterials KW - Nano-objects KW - Nanoparticles KW - Nanotechnology KW - Reference materials KW - Characterisation KW - Physico-chemical properties KW - Exposure KW - Risk PY - 2013 DO - https://doi.org/10.3109/17435390.2012.739664 SN - 1743-5390 SN - 1743-5404 VL - 7 IS - 8 SP - 1325 EP - 1337 PB - Informa Healthcare CY - London AN - OPUS4-29343 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -