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Notes: We describe an experiment that couples a high-resolution Fourier transform spectrometer (FTS) to a supersonic jet of radicals. A 1-mm-i.d. cylindrical SiC nozzle is resistively heated to 1500 K in order to decompose organic precursors and generate expansions of jet-cooled radicals. We have used this apparatus to pyrolyze alkyl nitrites to make alkoxy and nitric oxide radicals. The residence time of radicals in this hot nozzle is roughly 20 μs RONO→ΔRO+NO. We use the FTS to detect the IR absorption of the product NO (ν0=1876.1 cm−1) at resolutions as fine as 0.005 cm−1 FWHM. We observe the product NO from the pyrolysis of CH3CH2ONO to be rotationally cooled to roughly 50 K. The IR spectra indicate that the optical path length is about 3/4 cm and that the nitrites pyrolyze to produce approximately 1014 NO radicals cm−3 some 9 mm downstream from the nozzle. Our spectrometer is capable of detecting an absorption signal of 0.1% over a bandwidth of 100 cm−1 at 0.005 cm−1 resolution. Depending on the infrared cross section of the radical, this implies that we are able to monitor diatomic radical densities of roughly 5×1012 cm−3 (quantum state)−1. © 1995 American Institute of Physics.

Notes: Construction has traditionally constituted one of the problem areas in the preparation of industry price and quantity statistm with in the system of national accounts of most countries. The difficulty stems from what is considered to be the unique character of construction projects. This has unnecessarily impeded the calculation of output price indexes and has resulted in the use of various input-based prices as proxies for output prices.One of the objectives of the development of the system of construction price statistics described in this paper is to permit deflation of the outputs of construction industries in order to produce industry output data in constant prices in a manner consistent with measures for the rest of the economy. This is a more promising approach to improving constant price industry and expenditure measures within the SNA framework than attempting such improvements through the collection of a vast array of quantity data.Construction industries sell specified configurations of materials-in-place which are, to borrow the jargon of other fields, sub-assemblies of some total system. As in other areas of industrial pricing, some of these products are simple and some are complex. Trade contractors sell these sub-assemblies or commodities mainly to an owner-builder or to a general contractor who, in turn, resells the trade contractors’ commodities along with whatever sub-assemblies the general contractor has produced. These sub-assemblies, when combined with, for example, the relevant outputs (or sub-assemblies) of manufacturers, the design services of service industries and the purchasers’ own contributions, yield the wide variety of plant and structures which constitute the various classes of gross fixed capital formation, which are not typically solely the outputs of the construction industries.The resulting contractors’ selling price indexes will provide deflators for the whole range of outputs of the various construction industries. These will become part of the system of industry selling price indexes from which relevant indexes for the various goods and services can be selected and combined with appropriate weights to yield arrays of deflators for the highly complex capital expenditures of business, institutions and government.Ultimately this integrated system of construction industry statistics will permit the preparation of gross output and value added measures, in both current and constant prices, to be calculated for the construction industries as an integral part of the Canadian System of National Accounts, as well as provide a key element for improving the deflation of fixed capital formation.

Notes: This paper explains the process of defining, measuring and costing health service outputs (Health Resource Groups – HRGs). It identifies why the introduction of HRGs became necessary and how they were rolled out and became mandatory. The steps followed to achieve national uniformity are explained. Evidence is provided on the extent to which HRGs have been adopted and on the wider roles they may fulfil, such as benchmarking. The possible implications for resource allocation and the power of clinicians are discussed. Finally, attention is turned to the possible consequences of costed HRGs, as a means of achieving detailed financial accountability at operational level and to alternative means of control.

Notes: We report here on an experiment in which picosecond electron pulses, produced by a compact radiation frequency (rf) electron gun, were used to excite a rectangular waveguide, generating 5 ps pulses of radiation with a bandwidth of ∼200 GHz. The interaction of the electron pulses with the waveguide can be modeled quite simply by performing a harmonic expansion of the pulse train produced by the electron gun and employing Poynting's theorem to compute the power coupled into the modes of the waveguide by each harmonic. The resulting model for the distribution of spectral power yields good agreement with the observed spectrum. © 1995 American Institute of Physics.