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We describe and demonstrate a method of creating arrays of patterned, individual, single-walled carbon nanotubes, including the spectroscopic mapping of the array. The process consists of creating networks of nanotubes suspended between silicon pillars, which are then transferred onto other substrates by an innovative process of direct stamping. Raman spectroscopy is used to spatially map and assign the specific properties of the suspended network prior to transfer. This method provides a simple and inexpensive means for deriving nanoscale devices utilizing individually assigned carbon nanotubes in a robust and non-surface-specific technique.

The integration of suspended carbon nanotubes into micron-scale silicon-based devices offers many exciting advantages in the realm of nano-scale sensing and micro-and nano-electromechanical systems (MEMS and NEMS). To realize such devices, simple fabrication schemes are needed. Here we present a new method to integrate carbon nanotubes into silicon-based devices by applying conventional micro-fabrication methods combined with a guided chemical vapor deposition growth of single-wall carbon nanotubes. The described procedure yields clean, long, taut and well-positioned tubes in electrical contact to conducting electrodes. The positioning, alignment and tautness of the tubes are all controlled by the structural and chemical features of the micro-fabricated substrate. As the approach described consists of common micro-fabrication and chemical vapor deposition growth procedures, it offers a viable route toward MEMS-NEMS integration and commercial utilization of carbon nanotubes as nano-electromechanical transducers.

The textual evidence from ancient Judah is mainly limited to ostraca, ink-on-clay inscriptions. Their facsimiles (binary depictions) are indispensable for further analysis. Previous attempts at mechanizing the creation of facsimiles have been problematic. Here, we present a proof of concept of objective binary image acquisition, via Raman mapping. Our method is based on a new peak detection transform, handling the challenging fluorescence of the clay, and circumventing preparatory ink composition analysis. A sequence of binary mappings (signifying the peaks) is created for each wavelength; their legibility reflects the prominence of Raman lines. Applied to a biblical-period ostracon, the method exhibits high statistical significance.

The ion-neutral friction (incluchng mass loachng) happens to be insufficient to support the magnetic baxrier at comet Halley trader conventional parmneters of ion-neutral interaction. It is shown that a centrifugal force resulting front the transverse plasma motion should be added to the momentum balance in order to explain the observed magnetic field structm'e. The radial profile of the transverse plasma velocity is derived fi'om the best fit with magnetic field data. The transverse velocity reaches •8 km s -! at. 10,000 km h'om the nucleus. Tiffs value depends httle on both the ion-neutral momentum exchange rate and the comet production rate, whence one may conclude that it is centrifugal force which dominates in the momentran balas•ce at this distance. 1. INTRODUCTION A ,--4000-km radius diamagnetic cavity surrounding the comet nucleus was discovered during the Giotto flyby near comet Halley [Neubauer et al., 1986]. The magnetic signature of this cavity resembles that of the ionopause of Venus [Russell et al., 1979]. The magnetic barrier exists upstream of the cavity, and the magnetic pressure in the barrier approximately equals the dynamic pressure of the solar wind flow. The magnetic field drops drastically at the cavity boundary (which is •20 km thick) and is a. lnmst absent inside the cavity. However, the plasma signature of tl•c diamagnetic cavity of Venus strongly diffc. rs from that for cmnet Halley. The cold plasma density starts to increase rapidly at the diamagnetic cavity near Venus [Brace et al., 1979] so that this bonndary also represents the ionosphere bound-and Korosmezey, 1986; Huntress et al., 1980] and the neutral gas production rate [Krankowsky et al., 1986] result in a maximum magnetic field strength in the barrier of 25 nT, which is only • 40% of the observed value (see also Haerendel [1987, Table 1]). Second, it is rather surprising that the agreement with the observations happens to be better for less realistic assumptions of plane magnetic field geome-17,045 A.I. Ershkovich, Z.M. Ioffe, and P.L