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311.
Volume Contents
Contents to Volume 7 相似文献312.
The aesthetic quality of fourteen beaches in the Firth of Forth, Scotland was surveyed between May and July 2002 using a protocol designed by the UK's National Aquatic Litter Group (NALG). Local authority beach cleaning regimes influence the amount of litter found on beaches. Frequent and thorough beach cleaning is necessary to maintain high aesthetic standards. Bathing and amenity beaches achieved higher aesthetic quality than non-bathing and non-amenity beaches. The aesthetic quality of rural and urban beaches was very similar. The NALG protocol appears more complicated to use than other beach litter surveys. However, the classification system generates results that are easily interpreted by the general public. Furthermore, the NALG protocol could be combined with coastal zone management plans as a useful environmental performance indicator. 相似文献
313.
Jielun Sun Donald H. Lenschow Sean P. Burns Robert M. Banta Rob K. Newsom Richard Coulter Stephen Frasier Turker Ince Carmen Nappo Ben B. Balsley Michael Jensen Larry Mahrt David Miller Brian Skelly 《Boundary-Layer Meteorology》2004,110(2):255-279
Using the unprecedented observational facilities deployed duringthe 1999 Cooperative Atmosphere-Surface Exchange Study (CASES-99),we found three distinct turbulent events on the night of 18October 1999. These events resulted from a density current,solitary wave, and internal gravity wave, respectively. Our studyfocuses on the turbulence intermittency generated by the solitarywave and internal gravity wave, and intermittent turbulenceepisodes associated with pressure change and wind direction shiftsadjacent to the ground. Both the solitary and internal gravitywaves propagated horizontally and downward. During the passage ofboth the solitary and internal gravity waves, local thermal andshear instabilities were generated as cold air was pushed abovewarm air and wind gusts reached to the ground. These thermal andshear instabilities triggered turbulent mixing events. Inaddition, strong vertical acceleration associated with thesolitary wave led to large non-hydrostatic pressure perturbationsthat were positively correlated with temperature. The directionaldifference between the propagation of the internal gravity waveand the ambient flow led to lateral rolls. These episodic studiesdemonstrate that non-local disturbances are responsible for localthermal and shear instabilities, leading to intermittentturbulence in nocturnal boundary layers. The origin of thesenon-local disturbances needs to be understood to improve mesoscalenumerical model performance. 相似文献
314.
Tero Niiranen Irmeli Mänttäri Matti Poutiainen Nicholas H. S. Oliver Jodie A. Miller 《Mineralium Deposita》2005,40(2):192-217
Sodic alteration is widespread in Palaeoproterozoic greenstone and schist belts of the northern Fennoscandian shield. In the Misi region that forms the easternmost part of the Peräpohja schist belt, several small magnetite deposits show intimate spatial relationships with intensely albitised gabbros, raising the possibility that regional sodic alteration released iron, which was subsequently accumulated into deposits. Two of these magnetite deposits, Raajärvi and Puro display a typical paragenesis as follows (from oldest to youngest): (1) diopside, (2) actinolite/tremolite-magnetite ± chlorite, biotite, and (3) serpentine ± hematite, chlorite. Mass balance calculations suggest that significant amounts of Fe, Ca, Mg, K, Cu, V, and Ba were lost, and Na and Si gained during the albitisation of the gabbro, at near-constant Al, Ga, Ti, and Zr. Significant amounts of Si, Ca, Fe, and Na were enriched in the formation of skarn related to magnetite deposits. Fe and V leached from country rocks deposited during the skarn-alteration and formed the vanadium rich iron deposits while Cu passed through the system without significant precipitation due to low sulphur fugasity. Variations in Na, Ca, Mg, K, and Ba contents reflect the composition of the infiltrating fluid during alteration. Conventional heating-freezing measurements and proton-induced X-ray emission (PIXE) analyses of the fluid inclusions related to actinolite/tremolite-magnetite stage alteration indicate that the fluids that caused the alteration and the Fe-mineralisation were complex, oxidised, highly saline H2O ± CO2 fluids that contained high amounts of Na, Ca, K, Fe, and Ba as well as elevated concentrations of Cu, Zn, and Pb. The oxygen isotope thermometry suggest that temperature during the Fe-mineralisation stage was between 390 and 490°C. Calculated δ18Ofluid values of 6.1–9.8‰ SMOW and δ13C values of calcites in the ores and skarns were between ?7.7 and 10.9‰ PDB and most likely reflect admixture of 13C depleted, possibly magmatic fluids with the marble wall rocks that show δ13Ccalcite values of 13‰ PDB. The SIMS U–Pb data on the zircons in the albitised gabbro next to the Raajärvi and Puro deposits suggest that intrusion of the gabbro took place at 2123±7 Ma and was accompanied by the formation of diopside skarn. The TIMS data on the metasomatic titanites related to sodic alteration yielded ages of 2062±3 and 2017±3 Ma. Iron was probably stripped from the mafic country rocks by sodic alteration between 2123 and 2017 Ma, driven by repeated brine influxes. Subsequently, the metal-rich brine was focused by a fault system and the iron was precipitated from this fluid by a combination of wall rock reaction, fluid mixing, and a drop in the temperature. 相似文献
315.
James B. Holt Jacqueline W. Miller Timothy S. Naimi Daniel Z. Sui 《Geographical review》2006,96(4):523-542
ABSTRACT. Levels of alcohol consumption are a major public health issue. This study aims to gain a better understanding of how geographical patterns of religious affiliation in the United States relate to geographical patterns of alcohol consumption. We explored state‐level correlations between alcohol consumption and religious adherence. Although we found no statistically significant correlation between overall religious adherence rates and current or binge drinking rates, states with higher adherence rates were significantly more likely to have high proportions of binge drinking among current drinkers. Yet, regionally, we found a strong inverse correlation in the Southeast and a strong positive correlation in the Midwest and Northeast between adherence rates and current and binge drinking rates. These geographical differences were largely explained after stratifying by major religious denominational groupings. States with high Catholic adherence rates tended to have higher drinking rates, whereas states with high Evangelical Protestant adherence rates tended to have lower drinking rates. These findings suggest that the relationship between religion and alcohol may be denomination‐specific and challenge the lay perception that religious adherence per se is associated with less alcohol consumption and less excessive drinking among those who drink. 相似文献
316.
M. N. Khaikine I. N. Kuznetsova E. N. Kadygrov E. A. Miller 《Theoretical and Applied Climatology》2006,84(1-3):161-169
Summary Quantitative measurements of the impact of an urban environment on the thermal state of the atmospheric boundary layer are
presented. Temperature profiles up to the height of 600 m were obtained in a continuous series of measurements by three microwave
profilers MTP-5 located in different areas of Moscow. The influence of this large city on urban heat island (UHI) parameters
was estimated on occasions with stationary atmospheric processes and during cases with frontal passage. Two types of UHI were
identified: one with a dome of urban warmth at all levels, and another with a low warm dome in combination with a lens of
cold air above. 相似文献
317.
Mark Lacy Steve Rawlings Katherine M. Blundell & Susan E. Ridgway 《Monthly notices of the Royal Astronomical Society》1998,298(4):966-976
Multiwavelength imaging and spectroscopy of the z =0.708 radio galaxy 3C 441 and a red aligned optical/infrared component are used to show that the most striking aspect of the radio–optical 'alignment effect' in this object is due to the interaction of the radio jet with a companion galaxy in the same group or cluster. The stellar population of the red aligned continuum component is predominantly old, but with a small post-starburst population superposed, and it is surrounded by a low-surface-brightness halo, possibly a face-on spiral disc. The [O iii ] 500.7/[O ii ] 372.7 emission-line ratio changes dramatically from one side of the component to the other, with the low-ionization material apparently having passed through the bow shock of the radio source and been compressed. A simple model for the interaction is used to explain the velocity shifts in the emission-line gas, and to predict that the ISM of the interacting galaxy is likely to escape once the radio source bow shock has passed through. We also discuss another, much fainter, aligned component, and the subarcsecond-scale alignment of the radio source host galaxy. Finally, we comment on the implications of our explanation of 3C 441 on theories for the alignment effect. 相似文献
318.
Jinwon Kim Norman L. Miller Jai-Ho Oh Jun-Seok Chung Deukkyun Rha 《Global and Planetary Change》1998,19(1-4)
We present the hydrometeorology of eastern Asia during April 1995 simulated by the Regional Climate System Model. The amount and location of simulated monthly precipitation agrees well with observations. Soil water content variation was closely correlated with precipitation. Land-surface evaporation and the surface energy budget were strongly controlled by soil moisture content. A sensitivity test with reduced initial soil moisture content suggested that near-surface soil moisture spins up quickly after heavy precipitation events. However, variations in the initial soil moisture field may alter details of the simulated precipitation which can introduce further complexity in climate simulations. 相似文献
319.
In order to predict the behaviour of plumes from three deep ocean outfalls for sewage off Sydney, three-dimensional numerical modelling was used. The modelling suite was driven by data generated by an oceanographic monitoring station measuring wind, ocean currents, temperature and wave characteristics. Three different modelling phases are implemented daily, a nearfield model, a hydrodynamic model and a water quality model. Model output can be used by the New South Wales Environment Protection Authority to predict water quality at ocean beaches and inform the community. 相似文献
320.
We consider the problem of determining and predicting how the wave speeds in particular directions for a transversely isotropic (TI) medium depend on particular combinations of the density-normalized moduli Aij. The expressions for the qP and qSV velocities are known to depend on four moduli. Normally, we can only determine three independent parameters from qP data, or two from qSZ data, as the others have much lower sensitivity. The resolvable parameters are conveniently described by axial and off-axis parameters: for qP rays, P0°= A11, P90°= A33 and P45°=(A11+ A33)/4 + (A13+2A55)/2; and for qSV rays, S0°= S90°=A55 and S 45°= (A11+ A 33)/4- A13/2. These parameters control the magnitude of the squared-velocities on the axes and at approximately 45°. For an arbitrary TI medium, if the medium is perturbed in a way that preserves a particular parameter, then slowness points in the associated direction and mode witl be approximately preserved in the new medium. we refer to these parameters as ‘push-pins’, i.e. if a parameter is fixed, the associated part of the slowness surface is pinned in place. Because, these five push-pins only contain four independent moduli, we can only fix at most three push-pins. Perturbing one of the other parameters inevitably perturbs the other. Numerical results illustrating the linkage between two push-pins, when three are fixed, are presented. So-called anomalous TI media occur when the roles of the qP and qSV waves are reversed: in some directions the faster ray has transverse polarization. That, in turn, requires anomalous velocities at the push-pins, i.e. S0° > P0°, S45° > P45° and/or S90° > P90° (equivalent to the usual anomalous conditions A11 < A55, < 0 and/or A33 < A55). In the Appendix, we confirm that anomalous sensitivities of the velocities at the five push-pins only occur in such media, although the push-pins still apply if interpreted appropriately. Truly anomalous sensitivities, in which push-pins play no role, only occur in media near the boundary between normal and anomalous. 相似文献