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81.
Steve Herbert 《The Professional geographer》1997,49(1):86-94
Despite widespread interest in the relationship between the exercise of power and control of space, few current works in geography make explicit use of the concept of territoriality. This paper does so by considering the means by which the Los Angeles Police Department pursues its law enforcement and order maintenance functions through regulating space. I draw upon fieldwork observations of a single LAPD patrol division to demonstrate that officers regularly seek to govern the citizenry through controlling the spatial parameters of permissible action. The imperative toward effective territorial control is given further impetus within the subcultural world that officers construct; indeed, officers evaluate each other's competence in large part on their ability to manage activity within the spaces for which they are responsible. 相似文献
82.
Francesco Di Benedetto Ilaria Bencistà Francesco D’Acapito Silvia Frizzera Andrea Caneschi Massimo Innocenti Alessandro Lavacchi Giordano Montegrossi Werner Oberhauser Maurizio Romanelli Herbert Dittrich Luca A. Pardi Gerold Tippelt Georg Amthauer 《Physics and Chemistry of Minerals》2016,43(8):535-544
The successful synthesis of nanoparticles of Fe-bearing kuramite, (Cu,Fe)3SnS4, is reported in this study. Nanocrystalline powders were obtained through a mild, environmentally friendly and scalable solvothermal approach, in a single run. The sample was the object of a multidisciplinary investigation, including X-ray diffraction and absorption, scanning electron microscopy and microanalysis, electron paramagnetic resonance, diffuse reflectance and Mössbauer spectroscopy as well as SQUID magnetometry. The nanoparticles consist of pure Fe-bearing kuramite, exhibiting tetragonal structure. The valence state of the metal cations was assessed to be Cu+, Sn4+ and Fe3+. The material presents a band gap value of 1.6 eV, which is fully compatible with solar cell applications. The uptake of Fe by nanokuramite opens a compositional field where the physical properties can be tuned. We thus foster the application of Fe-bearing nanokuramite for photovoltaics and energy storage purposes. 相似文献
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A suite of high-resolution (10 km) simulations were performed with the International Centre for Theoretical Physics (ICTP) Regional Climate Model (RegCM3) to study the effect of various lateral boundary conditions (LBCs), domain size, and intermediate domains on simulated precipitation over the Great Alpine Region. The boundary conditions used were ECMWF ERA-Interim Reanalysis with grid spacing 0.75°, the ECMWF ERA-40 Reanalysis with grid spacing 1.125 and 2.5°, and finally the 2.5° NCEP/DOE AMIP-II Reanalysis. The model was run in one-way nesting mode with direct nesting of the high-resolution RCM (horizontal grid spacing Δx = 10 km) with driving reanalysis, with one intermediate resolution nest (Δx = 30 km) between high-resolution RCM and reanalysis forcings, and also with two intermediate resolution nests (Δx = 90 km and Δx = 30 km) for simulations forced with LBC of resolution 2.5°. Additionally, the impact of domain size was investigated. The results of multiple simulations were evaluated using different analysis techniques, e.g., Taylor diagram and a newly defined useful statistical parameter, called Skill-Score, for evaluation of daily precipitation simulated by the model. It has been found that domain size has the major impact on the results, while different resolution and versions of LBCs, e.g., 1.125° ERA40 and 0.7° ERA-Interim, do not produce significantly different results. It is also noticed that direct nesting with reasonable domain size, seems to be the most adequate method for reproducing precipitation over complex terrain, while introducing intermediate resolution nests seems to deteriorate the results. 相似文献
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Herbert A. Zook 《Planetary and Space Science》1975,23(10):1391-1397
The heliocentric radial distribution of the flux of hyperbolic cosmic dust particles, as measured by the Pioneer 8 and 9 spacecraft, is closely related to the radial variation of the spatial density of source or “parent” meteoroids. Within the limits of the experimental and theoretical uncertainties the spatial density of parent meteoroids, as deduced from the hyperbolic cosmic dust data, is found to be increasing with increasing heliocentric distance in the neighborhood of one a.u. Other recent experimental evidence confirms this result. The new results also suggest that the ratio of the areal density of submicron sized craters to the areal density of millimeter sized craters will be less on the north-south faces of lunar rocks than on the east-west faces of the same rocks. The changeinratio is not as large as previously thought, however. Finally it is noted that the solar system is not presently contributing significant amounts of dust to the interstellar medium though it may once have done so. 相似文献
87.
Herbert Frey 《Icarus》1975,25(3):439-446
It may be possible to understand the apparent intermittent nature of the post-eclipse brightenings and nonbrightenings of Io in terms of a nonuniform distribution of blue reflectors grouped in the hemisphere centered at 0° longitude. The dimensions required for such blue mirrors are consistent with very large craters. The high blue albedo of water frost and other ices makes these materials likely candidates for the reflectors. 相似文献
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