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991.
Wei Song Jianguo Liu Yongfeng Nie 《Frontiers of Environmental Science & Engineering in China》2010,4(1):59-64
Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy
and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil
sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis,
semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products
were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random
chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process.
This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid
oil products. 相似文献
992.
993.
Bioremediation is considered as one of the effective ways to deal with the pollution of natural water because of its high efficiency, low cost and causing no secondary pollution. The multiple microbial preparation is composed of bacteria that can transfer nutritive material harmless and some natural humic acid which can destroy algae. The qualified bacteria were selected, separated, and enriched from the water and bottom sediment of eutrophic lake. A field trial of bioremediation was carried out in 60 m3 of eutrophic water body in Yingze Lake of Anshan for four months. TN (total nitrogen), TP (total phosphorus), ammonia nitrogen, CODCr, and turbidity of the trial water and untreated water were measured termly. Contrastive analysis showed the mulriple microbial preparation can increase the water capacity of self-purification, decrease the turbidity, inhibit algae growth and improve water quality gradually at substantially lower cost. Thus the problem of lake eutrophication can be solved radically by bioremediation. 相似文献
994.
Neighbour recognition allows territory owners to modulate their territorial response according to the threat posed by each
neighbour and thus to reduce the costs associated with territorial defence. Individual acoustic recognition of neighbours
has been shown in numerous bird species, but few of them had a large repertoire. Here, we tested individual vocal recognition
in a songbird with a large repertoire, the skylark Alauda arvensis. We first examined the physical basis for recognition in the song, and we then experimentally tested recognition by playing
back songs of adjacent neighbours and strangers. Males showed a lower territorial response to adjacent neighbours than to
strangers when we broadcast songs from the shared boundary. However, when we broadcast songs from the opposite boundary, males
showed a similar response to neighbours and strangers, indicating a spatial categorisation of adjacent neighbours’ songs.
Acoustic analyses revealed that males could potentially use the syntactical arrangement of syllables in sequences to identify
the songs of their neighbours. Neighbour interactions in skylarks are thus subtle relationships that can be modulated according
to the spatial position of each neighbour. 相似文献
995.
Vronique Saint-Ges Marie-Claude Blis-Bergouignan 《Journal of Cleaner Production》2009,17(18):1644-1653
French and European incentives, such as Plan Ecophyto 2018, European directive for a sustainable use of pesticides, reinforce the requirement for vine-growers to engage in more environmentally friendly farming practices. In this respect, this paper presenting the results of a large questionnaire survey conducted in Bordeaux area vineyards and focusing on the behaviour of their vine-growers towards environmental innovations is particularly adequate. Founding that the most important environmental issue in vineyards relates to the use of pesticides, the paper characterizes the main economic and cognitive factors determining vine-growers' environmental innovations. It allows determining possible policies milestones, efficient and feasible, towards a more environmentally friendly vineyard. The paper first outlines the analytical framework, then highlights the main results and, finally, goes through further discussion and policy implications. 相似文献
996.
Introduction: E-scooter rider injuries have been growing, but little is known about how trip and incident characteristics contribute to their severity. Method: We enrolled 105 adults injured while riding e-scooters who presented to an emergency department in Washington, DC, during 2019. Enrolled participants completed an interview during the emergency department visit, and their charts were abstracted to document their injuries and treatment. Logistic regression examined the association of incident location and circumstances with the likelihood of sustaining an injury on the Abbreviated Injury Scale (AIS) ≥ 2, while controlling for rider characteristics. Results: The most common locations of e-scooter injuries in our study sample occurred on the sidewalk (58%) or road (23%). Accounting for other trip and rider attributes, e-scooter riders injured on the road were about twice as likely as those injured elsewhere to sustain AIS ≥ 2 injuries (RR, 1.96; 95% CI, 1.23–2.36) and those who rode at least weekly more often sustained AIS ≥ 2 injuries compared with less frequent riders (RR, 1.86; 95% CI, 1.11–2.32). Conclusions: Greater injury severity for riders injured on the road may reflect higher travel speeds. Practical applications: Injury severity associated with riding in the road is one factor that jurisdictions can consider when setting policy on where e-scooters should be encouraged to ride, but the risk of any crash or fall associated with facilities should also be examined. Although injuries are of lower severity on sidewalks, sharing sidewalks with slower moving pedestrians could potentially lead to more conflicts. 相似文献
997.
Introduction: Cycling is one of the main forms of transportation in Denmark. However, while the number of traffic crash fatalities in the country has decreased over the past decade, the frequency of cyclists killed or seriously injured has increased. The high rate of serious injuries and fatalities associated with cycling emphasizes the increasing need for mitigating the severity of such crashes. Method: This study conducted an in-depth analysis of cyclist injury severity resulting from single and multiparty bicycle-involved crashes. Detailed information was collected using self-reporting data undertaken in Denmark for a 12-month period between 1 November 2012 and 31 October 2013. Separate multilevel logistic (MLL) regression models were applied to estimate cyclist injury severity for single and multiparty crashes. The goodness-of-fit measures favored the MLL models over the standard logistic models, capturing the intercorrelation among bicycle crashes that occurred in the same geographical area. Results: The results also showed that single bicycle-involved crashes resulted in more serious outcomes when compared to multiparty crashes. For both single and multiparty bicycle crash categories, non-urban areas were associated with more serious injury outcomes. For the single crashes, wet surface condition, autumn and summer seasons, evening and night periods, non-adverse weather conditions, cyclists aged between 45 and 64 years, male sex, riding for the purpose of work or educational activities, and bicycles with light turned-off were associated with severe injuries. For the multiparty crashes, intersections, bicycle paths, non-winter season, not being employed or retired, lower personal car ownership, and race bicycles were directly related to severe injury consequences. Practical Applications: The findings of this study demonstrated that the best way to promote cycling safety is the combination of improving the design and maintenance of cycling facilities, encouraging safe cycling behavior, and intensifying enforcement efforts. 相似文献
998.
Introduction: The appearance of musculoskeletal disorders (MDs) in professional drivers due to exposition to whole-body vibration (WBV) makes it relevant to assess this exposure. The European Directive 2002/44/EC has two methods to evaluate exposure to WBV (defined in ISO2631-1:2008). These methods evaluate the exposure associated with an 8-hour working day; however, MDs due to WBV could also be caused by accumulated exposure to vibrations over long term, and hence, the methods defined in the European directive may be limited in their ability to ensure the safety of workers exposed to WBV throughout their years of employment. Method: A detailed comparison and discussion of methods defined in the European Directive and the ISO2631-5:2018 was used as a starting point of the main results of this paper. On this basis, a new methodology for the management and organization of preventive measures is proposed to consider the assessment of ISO2631-5:2018 standard and the full working life of workers. Experimental data to assess exposure to WBV in heavy equipment vehicle (HEV) drivers under different road surface conditions and range of velocities were considered to illustrate the process of the proposed methodology. Results: The methods defined in the standards provide different assessments leading to a different possible consideration of safe operations when the risks associated with them may actually be high. The proposed methodology can be used with the aim of ensuring safety of workers throughout their working lives and providing an easy implementation of the calculations of ISO2631-5:2018 standard. Conclusions: A procedure to assess the health risk probability to which the HEV worker is exposed in terms of the exposure years and a different range of operational vehicle speeds is proposed and exemplified with a study case. Practical applications: This study provides a practical tool for the management of WBV exposure related to work-tasks in HEV drivers. Safety managers should consider the global exposition to WBV throughout their working life, and this research provides an easy tool to accomplish it. 相似文献
999.
Introduction: In low-cycling countries, motor-vehicle traffic and driver behavior are well known barriers to the uptake of bicycles, particularly for utility cycling. Lack of separation between cyclists and faster-moving traffic is one key issue, while attitudes of drivers toward and/or harassment of cyclists is another. Cyclist-related driver education has been recommended as a means to improve driver-cyclist interactions. Methods: The driver licensing process provides an opportunity for such education. The Cycle Aware module was developed to test and enhance novice drivers’ knowledge of interacting safely with cyclists. It was piloted across three Australian jurisdictions targeting both novice and experienced drivers. Participants were asked to complete the Cycle Aware module and an accompanying survey. A total of 134 novice and 97 experienced drivers completed the survey with 42 novice and 50 experienced drivers going on to complete the module. Results: Both groups of drivers scored equally well in the module but the very youngest and very oldest participants were more likely to have some incorrect responses. We did not find any relationship between correct module scores and attitudes toward cyclists. Survey results showed both novice and experienced drivers had somewhat positive attitudes toward cyclists. The two cohorts differed on several attitude questions. Sixty percent (60%) of novices compared to 30% of experienced drivers reported feeling concerned when sharing the road with cyclists, and novices were less likely to agree that cyclists had a right to use the roads. Conclusions and practical applications: The analysis suggests novices need to be better equipped to share roads confidently with cyclists and to recognize cyclists as legitimate traffic participants. 相似文献
1000.
Introduction: Vehicular accidents at horizontal curves are over-represented compared to accidents that occur at tangent sections. Investigations have been conducted aimed at identifying the major causes that result in higher accident risk, both in terms of severity and rate, at curved road sections. Excessive or abrupt changes in speeding and improper vertical position are cited as major factors of lane departure, whereas other factors (either human or environmental) have also been documented. However, most research involves 4-wheel vehicles rather than other modes of transport that behave differently. More specifically, while motorcyclist fatalities occur more frequently than passenger vehicles, when accounting for vehicle distance traveled only a limited number of research studies address their behavior at curved road sections. Method: This paper presents the findings of field operational tests carried out by motorcyclists along two-lane rural roads with a wide range of horizontal curves using an instrumented motorcycle. Key objectives of the research included the conditions under which the motorcyclists differentiate their trajectory in regards to the direction of the horizontal curves, the correlation between the trajectory and the geometry of the road, and the impact of the lighting conditions on riders’ behavior. Results: The research showed that motorcyclists tend to ride closer to the centerline of the road, neglect the hazards associated with dim lighting conditions, and maintain constant speed in the left hand and the right-hand horizontal curves. 相似文献