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Mass spectrometric analysis of small negative ions (e/m < 100) produced by Trichel pulse negative corona discharge fed by ozonised air
Mass spectrometric analysis of small negative ions (e/m < 100) produced by DC negative corona discharge in ozonised wet air both in flow and flow-stopped regimes was conducted at pressure of 30 kPa. The point-to-plain electrode system has been used. The yield of individual ions is strongly affected by trace concentrations of ozone in both regimes. Ozone concentration greater than 25 ppm is sufficient to completely suppress the appearance of O2- and a NO2- ion as well as theirs clusters in the mass spectra. The temporal increase in concentration of NO3- ions and NO3-.(H2O)n (n = 1, 2) hydrated clusters was observed in flow-stopped regime accompanied by reduction in yield of CO3- ion and its water clusters CO3-.(H2O)n (n = 1, 2), which otherwise are the dominant ions in flowing wet air free of ozone. In contrast the addition of ozone into the flow of wet air resulted in evident increase in abundance of the clusters CO3-.(H2O)n (n = 1, 2). This is an evidence of an active role of nitrous oxide produced in flow-stopped regime in sufficient amount. The measured electrical conductivity of drift region confirmed the role of additional dissociative attachment of electrons by ozone molecules as well as a formation of clusters of lower mobility with increasing ozone concentration in the discharge gap
Low-dimensional long-range topological structure in the QCD vacuum
Lattice topological charge associated with Ginsparg-Wilson fermions exhibits
generic topological stability over quantum ensemble of configurations
contributing to the QCD path integral. Moreover, the underlying chiral symmetry
leads to the suppression of ultraviolet noise in the associated topological
charge densities ("chiral smoothing"). This provides a solid foundation for the
direct study of the role of topological charge fluctuations in the physics of
QCD vacuum. Using these tools it was recently demonstrated that: (a) there is a
well-defined space-time structure (order) in topological charge density
(defined through overlap fermions) for typical configurations contributing to
QCD path integral; (b) this fundamental structure is low-dimensional,
exhibiting sign-coherent behavior on subsets of dimension less than four and
not less than one; (c) the structure has a long-range global character
(spreading over maximal space-time distances) and is built around the locally
one-dimensional network of strong fields (skeleton). In this talk we elaborate
on certain aspects and implications of these results.Comment: 3 pages, 1 figure; Lattice2003(topology
Polyethylene imine-based receptor immobilization for label free bioassays
Polyethylene imine (PEI) based immobilization of antibodies is described and the concept is proved on the
label free assay of C-Reactive Protein (CRP). This novel immobilization method is composed of a hyperbranched
PEI layer which was deposited at a high pH (9.5) on the sensor surface. The free amino groups
of PEI were derivatized with neutravidin by Biotin N-hydroxysuccinimide ester and the biotinylated
anti-CRP antibody immobilized on this layer. Direct binding assay of recombinant CRP was successfully
performed in the low ÎŒg/ml concentrations using a label free optical waveguide biosensor
Advanced Very High Resolution Radiometer (AVHRR) data evaluation for use in monitoring vegetation. Volume 1: Channels 1 and 2
Data from the National Oceanic and Atmospheric Administration satellite system (NOAA-6 satellite) were analyzed to study their nonmeteorological uses. A file of charts, graphs, and tables was created form the products generated. It was found that the most useful data lie between pixel numbers 400 and 2000 on a given scan line. The analysis of the generated products indicates that the Gray-McCrary Index can discern vegetation and associated daily and seasonal changes. The solar zenith-angle correction used in previous studies was found to be a useful adjustment to the index. The METSAT system seems best suited for providing large-area analyses of surface features on a daily basis
A preliminary look at AVE-SESAME 1 conducted on 10-11 April 1979
Preliminary information on the general weather conditions during the AVE-SESAME 1 period is presented together with a summary of severe weather reports
Gravitational Waves from Wobbling Pulsars
The prospects for detection of gravitational waves from precessing pulsars
have been considered by constructing fully relativistic rotating neutron star
models and evaluating the expected wave amplitude from a galactic source.
For a "typical" neutron matter equation of state and observed rotation rates,
it is shown that moderate wobble angles may render an observable signal from a
nearby source once the present generation of interferometric antennas becomes
operative.Comment: PlainTex, 7 pp. , no figures, IAG/USP Rep. 6
Use of NOAA-N satellites for land/water discrimination and flood monitoring
A tool for monitoring the extent of major floods was developed using data collected by the NOAA-6 advanced very high resolution radiometer (AVHRR). A basic understanding of the spectral returns in AVHRR channels 1 and 2 for water, soil, and vegetation was reached using a large number of NOAA-6 scenes from different seasons and geographic locations. A look-up table classifier was developed based on analysis of the reflective channel relationships for each surface feature. The classifier automatically separated land from water and produced classification maps which were registered for a number of acquisitions, including coverage of a major flood on the Parana River of Argentina
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