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We present here a thorough photometric analysis of double-barred galaxies, consisting of (i) two-dimensional photometric decompositions including a bulge, inner bar, outer bar, and (truncated) disc; and (ii) three-dimensional statistical deprojections to derive the intrinsic shape of bulges, inner bars, and outer bars. This is the first time the combination of both techniques is applied to a sample of double-barred galaxies. It represents a step forward with respect to previous works, which are based on properties of the integrated light through ellipse fitting and unsharp masking. In this first paper of a series of two, we analyse the nature of the dominant bulges within double-barred systems by using several photometric diagnostics, namely Sérsic index, Kormendy relation, colours, and the better suited intrinsic flattening. Our results indicate that almost all bulges in our sample are classical, whereas only two out of the 17 galaxies under study appear as potential candidates to host secularly formed disc-like bulges. Such result poses the possibility that having a central hot structure may be a requirement for inner bar formation. [ABSTRACT FROM AUTHOR]

Soil-applied liquid termiticides are the most common control measure for subterranean termites. Characteristics unique to insecticidal chemistries such as repellency, toxicity, and time between contact and mortality, influence the interaction of termites with treated soil and overall treatment success. Two different treated-tunnel bioassays were used to evaluate the behavioral impacts and mortality of termites from treatment with chlorantraniliprole (the active ingredient in Altriset® termiticide) to existing, mature tunnels. Termites that were provided constant access to a 10-cm-long mature tunnel within soil treated with 5 or 50 ppm chlorantraniliprole were not repelled by the treatment and began exhibiting slower, uncoordinated movement, and cessation of tunneling and feeding in as little as 1 h after access. Termites provided access for 7, 14, or 21 d to previously constructed tunnels recently treated with 50 ppm chlorantraniliprole exhibited complete or near complete mortality by 28 d. The second bioassay design resembled a more typical field situation with a 40-cm-long mature tunnel and termites allowed access for a maximum of 5 min. Termites collected after just 5 min of access to the previously constructed tunnels recently treated with 50 ppm chlorantraniliprole exhibited similar symptomology within an hour followed by complete mortality at 18 d after exposure. These test designs simulate what occurs in the soil around an infested structure at the time of treatment. Results from these evaluations suggest that termites readily crawl through chlorantraniliprole-treated mature tunnels, rapidly lose ability to feed, and acquire a lethal dose from brief exposures. [ABSTRACT FROM AUTHOR]

Detailed knowledge of the physical form and chemical composition of brazing fume is important in assessing its health hazards as these are dependent upon the composition, deposition, toxicity and retention of the inhaled fraction. Fume produced from a commercial high cadmium brazing alloy and fluoroborate flux was collected and analysed by a variety of microanalytical techniques. The chemical composition and particle morphology were determined. The extremely complex nature of fume was revealed. Particulates observed included droplets, chains and homogeneous circular deposits, and the potential for lung deposition was high. Analysis showed that cadmium oxide and potassium fluoroborate were present in the fume as major constituents. Boron trifluoride and hydrogen fluoride gases have been reported above the melt and both have been implicated in the formation of several fume compounds. The results confirm the known effects of industrial exposures to brazing a fume. The risk from chronic and acute exposure to such fume must never be underestimated. [ABSTRACT FROM PUBLISHER]

Fluxes used in brazing can play a significant role in the transfer of cadmium from the surface of cadmium-bearing alloys to form fume. Experimental studies on the release of metals in inert atmospheres have shown that their concentrations above the alloy can be predicted from their vapour pressures. The presence of flux does not affect the relative concentrations of metals in the fume. The fume-formation rate is, however, intimately related to the characteristics of the flux. Acidic, freely bubbling fluxes yield highest fume-formation rates. The implications of these studies to the control of fume at source are discussed. [ABSTRACT FROM PUBLISHER]