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SummaryThis paper gives details of 397 radio sources between declina.tions + 20 0 and +27 0 which were compiled from a finding survey made at 635 MHz with the 210 ft reflector at the Australian National Radio Astronomy Observatory, Parkes, N.S.W.The survey covers an area of 0·703 steradian but is incomplete in two regions within ± 100 of the galactic equator. Additional measurements of flux densities and positions were made at 1410 and 2650 MHz. Some discussions on spectra, source counts, and source identifications are included, and a comparison is made between this survey and other published oatalogues oovering the same region. I. INTRODUOTIONThis paper is the fifth seotion of a survey for radio souroes being made with the 210 ft radio telescope at the Australian National Radio Astronomy Observatory, Parkes, N.S.W. The earlier parts of the survey have already been published and oover the declination zones 0° to +20° ), 0° to -20° (Shimmins et al. 1966), -20° to _60° (Bolton, Gardner, and Maokey 1964, and _60° to _90° (Prioe and Milne 1965). The present paper oovers the remaining deolination zone that is visible with the Parkes telesoope, +20° to +27°, and is oomplete except for two areas within ±10 0 of the galactio equator. The oatalogue oontains 397 souroes within O· 703 steradian, 341 of these souroes being outside the region ± 10° of the galaotio equator (effeotive area 0·606 steradian). The oatalogue is thought to be substantially oomplete down to a flux density of 1·5 f.u.t at 635 MHz outside the galaotio plane region but oontains some weaker souroes down to 0·8 f.u.The observations differ from those of the earlier seotions of the oatalogue in that the finding survey was done at a frequenoy of 635 MHz. Positions and flux densities were subsequently measured at 1410 and 2650 MHz.The estimated r.m.s. errors in position and the date of measurement are given for eaoh souroe in the oatalogue.

In recent years two 408 MHz surveys of the northern sky have been made to study the large-scale, low-surface-brightness features of the galactic background such as the loops and spurs (Haslam et al. 1970; Haslam et al. 1974). These surveys were designed to make maps down to the confusion limits of the telescopes used and to provide as far as practicable accurate calibration of the temperature scale and zero level for large-scale features. This work is complementary to the work of the large array telescopes; these telescopes can provide high resolution detail but they have lower surface brightness sensitivity, and have problems in determining the low-order terms which define the large-scale structure. The Parkes 408 MHz sourthern survey continues this work using the 64-m telescope to complete the coverage of the sky to the south pole. The project is a joint venture between the Max-Planck-Institut and CSIRO. For the southern survey it was felt desirable to measure the linear polarization distribution, besides making an accurate average temperature map in left-hand circular polarization (which is insensitive to variations of ionospheric Faraday effects). The previous surveys did not include linear polarization measurements.

Radio recombination line observations of the Carina nebula at 6 cm and 3.4 cm were made at Parkes. Around Carina II the profiles are separated by as much as 45 km s-1. This is interpreted as expansion in the H ii region.

Laboratory evaluations of commercially available powders of beryllium oxide (BeO) and beryllium metal, with special emphasis on type UOX-125 BeO and type I-400 beryllium metal, are ongoing to develop reference materials for evaluating analytical chemistry digestion methods and facilitating occupational health studies. Measured properties of the powders include morphology, size, density, specific surface area (SSA); crystalline and elemental composition; surface chemistry, and in vitro dissolution in hydrochloric acid (HCl) (pH 1), phagolysosomal simulant fluid (PSF) (pH 4.5), and serum ultrafiltrate (pH 7.3). The powders were also used to evaluate the digestion and recovery efficiencies for commonly used U.S. Environmental Protection Agency (EPA), National Institute for Occupational Safety and Health (NIOSH), and Occupational Safety and Health Administration (OSHA) standard analytical methods. UOX-125 BeO powder has high-purity and aggregate cluster morphology with SSA independent of aerodynamic particle cluster size, which results in dissolution kinetics that are independent of cluster size. I-400 beryllium metal powder has high-purity and compact particle morphology with SSA that increases as particle size decreases, which causes size-dependent dissolution kinetics (i.e., smaller particles dissolve more quickly than larger particles). The PSF and HCl chemical dissolution rate constants (g·cm−2day−1) for the BeO powder were a factor of 10 lower than for the metal powder. Concomitantly, the EPA and NIOSH analytical methods, which used aggressive digestion procedures (e.g., microwave-assisted sample digestion or perchloric acid), gave more complete recovery of beryllium from BeO compared to the OSHA analytical method. Our characterization data suggest that these BeO and metal powders hold promise for use as analytical reference materials. We recommend continued laboratory collaborations to evaluate and apply these BeO and beryllium metal powders as analytical reference materials.