Abstract. Cross sections and rate coefficients for total and fine-structure resolved charge transfer in collisions of O + with H and H + with O are presented for collision energies between 0.1 meV/u and 10 MeV/u and temperatures between 10 and 10 7 K. The results are obtained utilizing new quantal and semiclassical molecular-orbital closecoupling, classical trajectory Monte Carlo, and continuum distorted wave calculations in conjunction with previous experimental and theoretical data. Applications to various astrophysical and atmospheric environments are discussed.

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This article reports on a new charging process and Coulomb-force-directed assembly of nanoparticles onto charged surface areas with sub-100-nm resolution. The charging is accomplished using a flexible nanostructured thin silicon electrode. Electrical nanocontacts have been created as small as 50 nm by placing the nanostructured electrode onto an electret surface. The nanocontacts have been used to inject charge into 50 nm sized areas. Nanoparticles were assembled onto the charge patterns, and a lateral resolution of 60 nm has been observed for the first time. A comparison of the nanoparticle patterns with the surface potential distribution recorded by Kelvin probe force microscopy (KFM) revealed a mismatch in the lateral resolution. One possible explanation is that nanoparticles may visualize charge patterns at a sub-60-nm length scale that is not well resolved using KFM.Inorganic, metallic, and semiconducting nanomaterials in the form of nanoparticles, nanowires, nanobelts, or nanodisks are considered key building blocks in the design of novel high-performance nanotechnological devices. The process to fabricate such devices, however, will require new additive concepts to integrate, orient, and assemble such building blocks at desired locations on a substrate. Current approaches that address the integration of nanomaterials at desired locations on a substrate include serial scanning probe based concepts to print 1,2 or manipulate 3 nanomaterials at the sub-100-nm length scale, semiparallel inkjet-based concepts 4,5 to print materials from suspensions with 10 µm scale resolution, parallel nanotransfer methods 6,7 to transfer nanomaterials from one substrate to another retaining a copy of the order, and a vast variety of programmable or "receptor based" assembly concepts 8-18 that use unordered nanomaterials as an input. Scanning probe and inkjet-based methods enable rapid reconfiguration of the patterns and the formation of heterogeneous assemblies at an early stage but remain too slow to print materials over large areas at the sub-10-µm length scale. Nanotransfer concepts are most suitable to transfer nanomaterials from one substrate to another over large areas. Nanotransfer maintains the arrangement of the nanomaterials on a donor substrate; i.e., it does not order or rearrange the materials as part of the process."Receptor"-based concepts focus on the directed assembly of randomly oriented nanomaterials. The materials are suspended in solution or gas phase and are assembled at desired locations (receptors) on a substrate using specific interactions. Most actively investigated areas, currently, use protein recognition, 19,20 DNA hybridization,9,21,22 hydrophobicity/hydrophilicity, surface tension and self-assembled monolayers, 10 topography-directed concepts, 23-25 magnetic 11 and dielectrophoretic assembly and transport, 22,[26][27][28] and electrostatic forces. [12][13][14][15][16][17][18]25,27 In recent years there has been an increased focus on the use of long range electrostatic forces to direct th...

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Abstract-In this paper, we present the design, control, and testing of a 6 degrees-of-freedom magnetically-levitated system with nanometer-precision positioning capability and several-hundred-micrometer travel range. This system levitates a triangular single-moving-part platen, and produces the six-axis motion with six single-axis linear actuators. One of the prominent advantages of this magnetic levitation (maglev) system is that there is no physical contact between the moving part and the stator, which eliminates friction, wear, backlash, and hysteresis. As compared to other traditional devices, the present system is very compact with the minimum number of actuators for six-axis motion generation. The maglev device presented herein shows the position resolution better than 5 nm with 2-nm rms position noise, and is capable of a velocity of 0.5 m/s and an acceleration of 30 m/s 2 . The nominal power consumption is only 15 mW by each horizontal actuator, and 320 mW by each vertical actuator. The actuators are sized to be able to orient and position a maximum payload of 1 kg. The key application of this maglev device is the manipulation at nanoscale for microassemblies and manufacture of their parts. Other potential applications are stereolithography, vibration-free delicate instrumentation, and microscale rapid prototyping.