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Helium ion microscopy (HIM) is a relatively new high-resolution nanotechnology imaging and nanofabrication tool. HIM offers a near-molecular resolution (approaching that of TEM) combined with a simplicity of sample preparation and high depth of field similar to SEM. Simultaneously, the technique is not limited by the surface roughness as scanning probe microscopy (SPM) techniques or by the surface charging or radiation damage like SEM. In our review, we consider general principles, advantages, and prospects of HIM application in polymer science. Examples of high-resolution imaging of polymer-based nanocomposites, polymer nanoparticles, nanofibers, nanoporous materials, polymer nanocrystals, biopolymers, and polymer-based photovoltaic and sensor devices are presented. We compare the HIM’s applicability with other modern imaging techniques: SPM and SEM.

Plastic scintillators (PS) allow design of portative lightweight devices for quantification of low‐activity radiation sources. We have recently suggested a new type of organic fluorophores based on triphenyl pyrazoline (PZ) derivatives with high fluorescence quantum yield showing high radioluminescence when combined with a polyvinyltoluene (PVT) matrix. In this publication we report on radioluminescence properties of the PZ−X family with various halogen substitution (X=F, Cl, Br, I), or having vinyl functional group (vPZ, X=vinyl). PS based on such fluorophores and PVT matrix can be prepared as bulk samples, micrometer size beads or cladding on optical fibers. Application of fluorophores with vinyl functional groups enabled their enhanced interaction with the matrix due to covalent bonding between the components. We demonstrate high performance of PZ−X fluorophores and especially vPZ fluorophore in fabrication of nanocomposites for detection of various types of radiation. Scintillators have enhanced gamma ray detection capabilities with an addition of triphenyl Bi, or Gd2O3 nanoparticles. High fluorescence quantum yield and luminosity of PZ fluorophores allows dramatical reduction of their content in PS systems. Mechanisms of energy transfer and conversion during scintillation process are discussed. Special consideration is given to enhancement of α/β and neutron/gamma (n/γ) pulse shape discrimination (PSD) function of the developed scintillators. [ABSTRACT FROM AUTHOR]

Frictional characteristics of several types of boundary lubricants were tested using scanning probe microscopy (SPM). These include Langmuir monolayers of stearic acids (STA), their cadmium salts (STCd), self-assembling monolayers (SAMs) of alkylchlorsilanes, and complexes of STA with rigid naphthoylene benzimidazole (x-NBI) fragments. We observed that a Langmuir monolayer deposited on a silicon surface had a very low friction coefficient against a silicon nitride tip (about 0.01-0.05) but also low mechanical stability. SAMs were found to be much more stable but had the drawback of growth in the friction coefficient at high sliding velocities. Composite NBI/STA monolayers were much more stable and were not damaged by the highest normal load applied. The frictional behavior of different monolayers was analyzed in relation to their structural organization (the type of tethering to the surface and packing density). We introduced a figure of merit (FOM) parameter which allowed comparison of frictional properties of very different lubricant materials to those of the supporting substrate. For Langmuir monolayers the FOM increased strongly with surface packing density whereas for SAMs and x-NBI/STA complexes it possessed a maximum at surface densities in the range 3.5-4.5 molecules per [nm.sup.2]. Because of the possibility of tailoring the surface packing density of aliphatic tails in the complexes, they are a promising alternative to both LB films and SAMs. For such composite monolayers, the surface packing density can be optimized to give a desired frictional behavior.