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Notes: The evolution of surface morphologies of films prepared by ion-based deposition techniques has been investigated by atomic force microscopy. Two deposition processes, filtered arc deposition (FAD) and ion-beam-assisted deposition, where low-energy (〈100 eV) ion irradiation and high-energy (several tens of keV) ion-beam bombardment concurrent with film growth were involved, respectively, have been employed to prepare TiN and Al films. Comparative studies on the effect of energetic ions on the development of topography have been performed between the low-ion-energy regime and high-ion-energy regime. In addition, the relationship between topography and mechanical properties of thin films has been revealed, by involving thin films prepared by thermal evaporation deposition (TED), where almost all depositing particles are neutral. In the images of the TED TiN and Al films, a large number of porous and deep boundaries between columnar grains was observed, suggesting a very rough and loose surface. In contrast, the FAD films exhibited much denser surface morphologies, although still columnar. The root-mean-square roughness of the FAD films was less than 1 A(ring). Hardness test and optical parameter measurement indicated that the FAD films were much harder and, in the case of optical films, much more transparent than the TED films, which was considered to arise from the denser surface morphologies rather than crystallization of the films. The high density and super smoothness of the FAD films, and the resultant mechanical and optical properties superior to those of the TED films, were attributed to the enhancement of surface migration of the deposited adatoms in the FAD process, which could provide intensive low-energy ion irradiation during film growth. As for topography modification by high-energy ion-beam bombardment concurrent with film growth, in addition to the increase of surface diffusion due to elastic collision and thermal spikes, physical sputtering must be considered while explaining the development of the film topography. Both surface migration enhancement and sputtering played important roles in the case of high-energy heavy-ion-beam bombardment, under which condition surface morphology characterized by dense columns with larger dimension and deep clean boundaries was formed. However, under high-energy light-ion-beam bombardment, the sputtering was dominant, and the variation of sputtering coefficient with position on the surface of growing film led to the formation of cones. © 1996 American Institute of Physics.

Notes: Seebeck, electrical, and thermal conductivity data are reported on CoSb3, and doped and undoped alloys of Co1−xIrxSb3−yAsy from 20 to 700 K. n-type semiconductors were obtained by doping with Ni, Te, or Pd, and the hole concentration in p-type samples was increased by substitution of Fe, Ru, Os, and Ge. An estimated maximum value for ZT of 0.6 (Z is the figure of merit) was found for a Te-doped (n-type) alloy at 700 K. For p-type alloys, the maximum value of ZT was found to be 0.3 at 550 K. Electrical and thermal transport data also are reported for CoAs3, RhSb3, and IrSb3. Most of the samples investigated were polycrystalline, but a few measurements on CoSb3 single crystals also are discussed. © 1995 American Institute of Physics.

Notes: . This paper uses new estimates of metropolitan factor demand and output supply functions to study how federal, state, and local fiscal policies affect metropolitan economies. We illustrate our work with findings for ten metropolitan areas in five states for changes in state corporate income taxes, local property taxes, the federal corporate income tax, an investment tax credit, interest rates, public capital stocks, output prices, and tax and regulatory policies affecting gross wages. It is clear from these simulations that a policy that is nominally the same everywhere will have repercussions that vary widely across regions and cities.

Notes: . In this study we use a translog profit function and iterate seemingly unrelated regressions to estimate a system of factor demand and output supply functions for metropolitan economies. Our sample includes all metropolitan areas defined by the Census in 1977 for the period 1962 to 1982. Estimation shows that all price elasticities are elastic and that the signs are as expected. These results hold true for virtually all model specifications. Our findings indicate that federal, state, and local tax policies have significant impacts on factor demand and output supply. Public investment plays a positive and significant, but small, role in increasing output and in complementing other factors, although this influence has declined over time. Additionally, capital provided by the private sector has a substantially larger impact on output and employment than does capital provided by the public sector.

Notes: Objectives To estimate the prevalence and incidence in primary care of chronic pelvic pain in women in the UK.Design Cross-sectional analysis of MediPlus UK Primary Care Database. Setting One hundred and thirty-six general practices in the UK.Population From 284,162 women aged 12–70 who were registered on the database and who had a general practice contact in 1991,24,053 chronic pelvic pain cases were identified between 1991 and 1995.Methods Chronic pelvic pain was defined as pelvic pain lasting for at least six months, and cases were identified on the basis of contacts with general practice. Pain due to malignancy, chronic inflammatory bowel diseases or pregnancy, or which occurred only during menstruation or sexual intercourse, was excluded.Main outcome measures Prevalence and incidence rates of chronic pelvic pain in primary care by age and region.Results Monthly prevalence and incidence rates of chronic pelvic pain were 21.5/1000 and 1.58/1000, respectively, with an annual prevalence of 38.3/1000. Monthly prevalence rates increased significantly with age (P 〈 0.001) from 18.2/1000 in 15–20 year olds to 27.6/1000 in women older than 60, as symptoms persisted longer in older women. Prevalence and incidence rates varied significantly between regions (P 〈 0.001), with the lowest monthly prevalence in Scotland (16.0/1000) and the highest in Wales (29.4/1000).Conclusions Chronic pelvic pain is a common condition in the UK, with a prevalence in primary care comparable to migraine, back pain, and asthma. Its prevalence in the general population is likely to be considerably higher.

Notes: In RFX a monitor for the measurement of the on-axis electron temperature with high temporal resolution has been designed and operated during the last experimental campaigns. It consists of four soft x-ray (SXR) diodes which observe the plasma through four beryllium filters of different thickness. In this article the main design issues are presented. The measured values of the temperature, computed both with the standard double foil method and with a fit of all the available signals, are reported, correlated with the main plasma parameters and briefly compared with the results of other diagnostics. The main causes of systematic error, the effect of the noise and the reliability of the results in various plasma conditions have been investigated. Dynamic evaluations of the temperature up to a maximum bandwidth of 5 kHz are described, confirming the potentialities of the technique to follow fast phenomena. Possible improvements of the diagnostic and future developments are also pointed out. © 1999 American Institute of Physics.

Notes: High yields of highly charged ions are produced with electron beam ion sources (EBISs) operated in a batch or pulsed mode, yielding small duty cycles. An EBIS operated in a continuous, dc, or leaky mode can produce continuous, "dc'' ion beams, although with substantially lower yields especially for the higher charge states. This article introduces the leaky batch mode and the dc batch mode of operation which combine the high duty cycles obtained with leaky or dc modes with the high yields of highly charged ions obtained with batch modes. The leaky batch mode produces ion beams with duty cycles as high as 90% with ion yields as high as 70% of the most efficient batch mode. The dc batch mode delivers constant intensity (dc) ion beams during 50% of the time with ion yields as high as 98% of the most efficient batch mode. When the dc batch mode is combined with the stretcher mode proposed by Becker, the dc batch mode will allow for dc ion beams of constant intensity with yields close to the most efficient batch mode. © 1996 American Institute of Physics.

Notes: Electron beam ion sources produce very highly charged ions most efficiently in a batch mode as the confinement time can be directly optimized for the production of the desired charge state. If, after confinement, the voltage of the ion-confining downstream dam is lowered rapidly, all ions escape and form an ion beam pulse with a length of a few tens of μs. Raising the main trap voltage while maintaining a constant dam voltage in a "spill-over expulsion" reduces the energy spread of the expelled ions. The longer time periods of "slow-," "leaky batch mode-," and "direct current (dc) batch mode-" expulsions allow for increasing the ion beam duty cycle. Combining the rapid expulsion with one of the latter methods allows for the expulsion of the ions of a single batch in many small microbunches with variable intervals, maintaining the low energy spread and the increased duty cycle of slow expulsions. Combining the "microbunching" with "dc batch mode production" and a multitrap operation will eventually allow for the production of equally intense ion bunches over a wide range of frequencies without any deadtime, and with minimal compromise on the most efficient production parameters. © 1998 American Institute of Physics.

Notes: Time-resolved electron-beam diagnostics have been developed for use with free-electron lasers (FELs) and associated electron sources, based on the techniques of secondary electron emission and optical transition radiation (OTR). The 32-channel OTR detector forms part of a high-resolution (0.18%) electron spectrometer with a time resolution of 50 ns. Variable-magnification optics allow the spectrometer to view single-macropulse spectra with widths in the range of 0.2%–7%; wider spectra are taken with several momentum settings. Design criteria for the spectrometer are presented, and experience of operating with the diagnostics over a range of FEL physics experiments is summarized. The spectrometer is used, in conjunction with optical diagnostics, in studies at FELIX of efficiency enhancement, pulse chirping, and stepped-undulator operation. © 1996 American Institute of Physics.