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241.
In recent model years, Ford vehicles have been equipped with a supplementary seat belt reminder system that flashes and chimes intermittently for up to 5 min if the driver is unbelted. Sound- and light-based belt reminder systems of various types are beginning to appear in the market place, and it is important to learn about their acceptance and ability to increase belt use. The present study was designed to ascertain consumer reaction and reported belt use regarding the Ford system. Personal interviews were conducted with 405 drivers of vehicles with the reminder system. Among the drivers, 67% said they had activated the belt reminder one or more times, 73% said that the last time this happened they fastened their belts, 46% said their belt use had increased since driving this vehicle, 78% said they liked the reminder system, and 79% said they wanted a reminder system like this in their next vehicle. Five percent had disabled the system. Part-time users were responsive to the reminder, for example, of those who said they currently used belts usually but not on some occasions, 70% said they fastened their seat belts the last time the reminder was activated and 76% said their belt use had increased. Five percent spontaneously mentioned the belt reminder as an especially disliked feature of their new vehicles, and 2% said their belt use had decreased since having it. The 7% of respondents who reported they used belts never or very occasionally were least responsive to the system. Overall, the Ford belt reminder system is being favorably received. 相似文献
242.
In the present study, the biologically active natural product dibenzyl trisulphide (DTS) which was previously isolated from the sub-tropical shrub Petiveria alliacea was transformed to methyl benzyl sulphonic anhydride (MBSA) using a "one pot" transformation method. The anhydride was evaluated for anti-microbial activities on the bacteria, Bacillus subtilis and Pseudomonas fluorescens and found to be 2.5 fold more effective than the commercial agents isoniazid and ampicillin in inhibiting the growth of B. subtilis, while on P. fluorescens it was 2.5, 5.0 and 10.0 fold more inhibitory than isoniazid, ampicillin and dibenzyl trisulphide, respectively. DTS was inactive on B. subtillis. The MIC value (microgram/spot) found for DTS on the plant pathogenic fungus, Cladosporium cucumerinum was 5.0 microgram/spot, while MBSA gave a value of 0.1 microgram/spot, compared with 1.25 and 0.16 microgram/spot for the commercial agents ketoconazole and nystatin, respectively. On the larval nematode (Meloidogyne incognita) MBSA inflicted 97.72% and 57.47% Abbotts nematicidal activities at 125.0 and 62.5 ppm, respectively, while DTS had no effect at 125.0 ppm. Nematodes which were immobilized by the low concentrations of MBSA were unable to re-activate when exposed to 10.0 ppm picrotoxin, thus suggesting that the anhydride nematicidal activity is independent of the GABA-ergic neurophysiological pathway.MBSA demonstrated a strong dose dependent radicular suppression effect (r=0.984), on the radicles of Latuca sativa germinating seeds. DTS was weakly active. 相似文献
243.
J. G. Arnold R. Srinivasan R. S. Muttiah J. R. Williams 《Journal of the American Water Resources Association》1998,34(1):73-89
ABSTRACT: A conceptual, continuous time model called SWAT (Soil and Water Assessment Tool) was developed to assist water resource managers in assessing the impact of management on water supplies and nonpoint source pollution in watersheds and large river basins. The model is currently being utilized in several large area projects by EPA, NOAA, NRCS and others to estimate the off-site impacts of climate and management on water use, non-point source loadings, and pesticide contamination. Model development, operation, limitations, and assumptions are discussed and components of the model are described. In Part II, a GIS input/output interface is presented along with model validation on three basins within the Upper Trinity basin in Texas. 相似文献
244.
Combustion of Tyre Pyrolysis Oil 总被引:6,自引:0,他引:6
P.T. Williams R.P. Bottrill A.M. Cunliffe 《Process Safety and Environmental Protection》1998,76(4):291-301
245.
R. J. Portier D. L. Sattler D. G. Hoover T. M. Davis S. E. Williams 《补救:环境净化治理成本、技术与工艺杂志》1998,8(4):95-105
Well-recovery networks coupled to immobilized microbe bioreactors (IMBRs) were installed at a 172-acre former wood preserving facility for the bioremediation of organic wood preservatives present in site groundwater. Free-phase creosote from the hardpan and soluble preservative fractions contained in subsurface groundwater were pumped separately to different holding tanks. Trace creosote fractions contained in the subsurface groundwater were further gravity separated in the holding tank. Immobilized microbial isolates evaluated in earlier laboratory and field pilot tests were established into two 40, 000-liter bioreactors for the biodegradation of all targeted consitituents. Microbial growth, dissolved oxygen, pH, nutrients, flow rate, and temperature were monitored in this in situ/ex situ bioremediation system. The process was used to remove the polycyclic aromatic hydrocarbon (PAH) and phenolic components of creosote and pentachlorophenol from contaminated groundwater. Data generated during the past 2 1/2 years indicate that 26 target compounds consistently are reduced to levels acceptable for discharge. Currently operating in Baldwin, Florida, this full-scale prototype is remediating the former wood preserving facility and is being used as a model system for the design and construction of new bioreactor systems needed at similar industrial sites in the United States and abroad. 相似文献
246.
Mrs Sue Hare is the education and information services coordinator of the UK Atmospheric Research and Information Centre (ARIC). Professor James Longhurst was recently the director of the ARIC and Joe Buchdahl its global climate change information services coordinator. Professor Longhurst is now head of the Department of Environmental Health and Science, University of the West of England, Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY. Kelvin Williams is a geography consultant and is head of geography at Ysgol y Creuddyn, Penrhyn Bay, Llandudno, Gwynedd LL30 3LB. The pedagogy of atmospheric issues is identified in the context of environmental education in this paper. The UK Atmospheric Research and Information Centre (ARIC) has developed an education programme which has responded to the dynamic issues relating to the atmosphere since the establishment of the ARIC in 1984. The main route for the teaching of atmospheric issues is identified as being through the UK's National Curriculum although public awareness of issues has increased through the media and more recently through government publicity campaigns. 相似文献
247.
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249.
Ecosystem dynamics in high-elevation watersheds are extremely sensitive to changes in chemical, energy, and water fluxes. Here we report information on yields of dissolved organic C, N, and P for the 1999 snowmelt runoff season from three high-elevation catchments in the Colorado Front Range, U.S.A.: Green Lake 4 (GL4) and Albion townsite (ALB) on North Boulder Creek and the Saddle Stream (SS), a tributary catchment dominated by alpine tundra. Dissolved organic carbon (DOC) concentrations in stream waters ranged from <1 to 10 mg C L-1, with the highest values occurring at the SS site. Dissolved organic nitrogen (DON) concentrations ranged from below detection limits to 0.28 mg N L-1 and were again highest at the tundra-dominatedsite. Dissolved organic phosphorus (DOP) concentrations were at or near detection limits throughout the season in all three catchments indicating a strong terrestrial retention of P. OnlyDOC showed a significant relationship to discharge. Yields of DOC in the three catchments ranged from 10.6 to 11.8 kg C ha-1 while yields of DON and DOP ranged from 0.32 to 0.41 and 0.02 to 0.08 kg ha-1, respectively. The relatively highyield of organic N and P relative to C from the highest elevationsite (GL4) was somewhat surprising and points to either: (1) a source of dissolved organic material (DOM) in the upper reaches of the catchment that is enriched in these nutrients or (2) theselective uptake and processing of organic N and P downstream ofthe sampling site. Additionally, seasonal changes in the relativeimportance of DOM precursor materials appear to result in changesin the N content of DOM at both the GL4 and ALB sites. 相似文献
250.
Lance R. Williams Christopher M. Taylor Melvin L. Warren Jr. J. Alan Clingenpeel 《Environmental management》2002,29(1):76-87
Using Basin Area Stream Survey (BASS) data from the United States Forest Service, we evaluated how timber harvesting influenced
patterns of variation in physical stream features and regional fish and macroinvertebrate assemblages. Data were collected
for three years (1990–1992) from six hydrologically variable streams in the Ouachita Mountains, Arkansas, USA that were paired
by management regime within three drainage basins. Specifically, we used multivariate techniques to partition variability
in assemblage structure (taxonomic and trophic) that could be explained by timber harvesting, drainage basin differences,
year-to-year variability, and their shared variance components. Most of the variation in fish assemblages was explained by
drainage basin differences, and both basin and year-of-sampling influenced macroinvertebrate assemblages. All three factors
modeled, including interactions between drainage basins and timber harvesting, influenced variability in physical stream features.
Interactions between timber harvesting and drainage basins indicated that differences in physical stream features were important
in determining the effects of logging within a basin. The lack of a logging effect on the biota contradicts predictions for
these small, hydrologically variable streams. We believe this pattern is related to the large scale of this study and the
high levels of natural variability in the streams. Alternatively, there may be time-specific effects we were unable to detect
with our sampling design and analyses. 相似文献