RILEM TC 267 TRM– “Tests for Reactivity of Supplementary Cementitious Materials” recommends the Rapid Reliable Relevant (R3) test as a method for determining the chemical reactivity of supplementary cementitious materials (SCMs) in Portland cement blends. In this paper, the R3 test was applied to 52 materials from a wide range of conventional and alternative SCMs with the aim to validate such test. An excellent correlation was found between the cumulative heat release and the bound water determined following the R3 test method. Comparison of the R3 test results to mortar compressive strength development showed that all conventional SCMs (e.g. blast furnace slag and fly ashes) followed the same trend, with the notable exception of very reactive calcined kaolinitic clays. It is discussed, through an in-depth statistical regression analysis of the R3 reactivity test results and the 28 days relative compressive strengths, how reactivity threshold values for classification of the chemical reactivity of SCMs could be proposed based on the R3 test results.@en

We report a novel method for the formation of hollow rod silicon nanostructures via plasma treated nanosphere lithography and reactive ion etching. The plasma treatment of polystyrene nanospheres (PS-NS) with O ₂ and methanol-O₂ gases is studied as a function of nanosphere size, plasma power and treatment time on a silicon substrate covered by a thin layer of nickel. Applying hydrogen or HCl plasma to already treated polystyrenes, nano-rings and nano-dots can be obtained without any physical or sputtering damage. Large area silicon nano-pillars and hollow silicon nano-structures with inner diameters of 50 nm were obtained by using optimized plasma treatment. These nanostructures show a hexagonal order with good fidelity to the PS-NS patterns. Various characterization techniques such as AFM, SEM, TEM, XPS and FTIR spectroscopy have been exploited to study the samples. The hollow rod structures made using this method will have applications in low power high performance electronic devices, optoelectronic and lithium ion battery devices. Also, a model for the formation of hollow rings is presented. This journal is

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