949 resultados para Street cleaning


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Gas-to-liquid processes are generally used to convert natural gas or other gaseous hydrocarbons into liquid fuels via an intermediate syngas stream. This includes the production of liquid fuels from biomass-derived sources such as biogas. For example, the dry reforming of methane is done by reacting CH4 and CO2, the two main components of natural biogas, into more valuable products, i.e., CO and H2. Nickel containing perovskite type catalysts can promote this reaction, yielding good conversions and selectivities; however, they are prone to coke laydown under certain operating conditions. We investigated the addition of high oxygen mobility dopants such as CeO2, ZrO2, or YSZ to reduce carbon laydown, particularly using reaction conditions that normally result in rapid coking. While doping with YSZ, YDC, GDC, and SDC did not result in any improvement, we show that a Ni perovskite catalyst (Na0.5La0.5Ni0.3Al0.7O2.5) doped with 80.9 ZrO2 15.2 CeO2 gave the lowest amount of carbon formation at 800 °C and activity was maintained over the operating time.

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A resazurin (Rz) based photocatalyst indicator ink is used to test the activity of a commercial self-cleaning glass, using UV–vis spectroscopy and digital photography to monitor the photocatalyst-driven change in colour of the ink. UV–vis spectroscopy allows the change in film absorbance, ΔAbs, to be monitored as a function of irradiation time, whereas digital photography is used to monitor the concomitant change in the red component of the RGB values, i.e. ΔRGB (red). Initial work reveals the variation in ΔAbst and ΔRGB (red)t as a function of irradiation time, t, are linearly correlated. The rates of change of these parameters are also linearly correlated to the rates of oxidative destruction of stearic acid on self-cleaning glass under different irradiances. This work demonstrates that a measure of photocatalyst activity of self-cleaning glass, i.e. the time taken to change the colour of an Rz photocatalyst indicator ink, can be obtained using inexpensive digital photography, as alternative to more expensive lab-based techniques, such as UV–vis spectrophotometry.

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Novel, reversible (reusable) photocatalyst activity indicator labels, which undergo a rapid colour change when in contact with a photocatalytic film via the photoreduction of methylene blue contained within the label’s adhesive, are explored as a method for assessing the activity of self-cleaning glass in situ and the laboratory, using digital photography.

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This article is based on an institutional ethnographic inquiry into the work of paramedics and the institutional setting that organizes and coordinates their work processes in a major City in Canada. Drawing on over 200 hours of observations and over 100 interviews with paramedics (average length of 18 minutes) and other emergency medical personnel, this article explores the standard and not so standard work of paramedics as they assess and care for their patients on the front lines of emergency health services. The multiplicity of interfacing social, demographic, locational, and situational factors that shape and organize the work of paramedics are analyzed. In doing so, this article provides insights into the complex work of an understudied yet ever-important profession in healthcare.

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An outlier removal based data cleaning technique is proposed to
clean manually pre-segmented human skin data in colour images.
The 3-dimensional colour data is projected onto three 2-dimensional
planes, from which outliers are removed. The cleaned 2 dimensional
data projections are merged to yield a 3D clean RGB data. This data
is finally used to build a look up table and a single Gaussian classifier
for the purpose of human skin detection in colour images.

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The Belfast city center is fractured, divided by motorways, parking lots, empty buildings, and big box stores. Its 19th-century heyday put it on the international map of textile production, which transformed and enriched its built structure. This tight architectural fabric was slowly destroyed in the 1940s by the Blitz, in the 1970s by road plans and “the troubles” and in the 1990s by large retail buildings. Few pedestrian streets traverse Belfast, and among them, most are recently-developed conduits for the passage of shoppers from one chain store to the next.Within this seemingly bleak urban landscape, there remain a few areas that offer a richer, more architecturally and socially diverse, more memory-laden conception of public space. Current redevelopment plans, however, threaten the mere existence of these few remaining historic streets in Belfast.This reality inspired the current project of one of the Masters in Architecture design units at Queen’s University Belfast. Our team (led by urban designer Michael Corr and myself) has been exploring North Street, one of the main arteries in Belfast City Center. Although North Street has a reputation for being run-down, derelict, and in need of redevelopment, it is one of the few intact 19th-century streets left in the area, and as such is worthy of study as an example of public space that is not strictly synonymous with commercial space.

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PURPOSE:

This study explored the gaze patterns of fully sighted and visually impaired subjects during the high-risk activity of crossing the street.

METHODS:

Gaze behavior of 12 fully sighted subjects, nine with visual impairment resulting from age-related macular degeneration and 12 with impairment resulting from glaucoma, was monitored using a portable eye tracker as they crossed at two unfamiliar intersections.

RESULTS:

All subject groups fixated primarily on vehicles and crossing elements but changed their fixation behavior as they moved from "walking to the curb" to "standing at the curb" and to "crossing the street." A comparison of where subjects fixated in the 4-second time period before crossing showed that the fully sighted who waited for the light to change fixated on the light, whereas the fully sighted who crossed early fixated primarily on vehicles. Visually impaired subjects crossing early or waiting for the light fixate primarily on vehicles.

CONCLUSIONS:

Vision status affects fixation allocation while performing the high-risk activity of street crossing. Crossing decision-making strategy corresponds to fixation behavior only for the fully sighted subjects.

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This paper presents a single case study of one street gang in one London borough. Semistructured interviews were conducted with 12 gang members, or former gang members, and seven practitioners. The practitioners and gang members / ex-gang members reported different perspectives on how the gang was structured and drug dealing was organised. The gang members / ex-gang members suggested that the gang is a loose social network with little recognisable formal organisation. Although individual gang members sell drugs, the gang should not be viewed as a drug dealing organisation. Rather it is a composition of individual drug dealers who cooperate out of mutual self-interest. Therefore, some gang members are best described as independent entrepreneurs while others are subcontractors looking to 'go solo'. The seven practitioners, however, tended to describe a more hierarchically structured gang, with formal recruitment processes. This divergence of perspective highlights an important consideration for policy and research.

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This is a due date card for the book titled Quality Street, stamped Works Progress Administration, District No. 3

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This paper written in Spanish gives hints on what to do to control mold after the flooding in October 2015 in South Carolina. Topics include: presence of mold after a flood, signs of mold, people at greatest risk for health effects from mold, possible health effects of mold exposure and cleaning wet or moldy Items after a flood. It also gives web sites for additional information and resources.

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In epidemiological studies, outdoor exposure to pollen is typically estimated using rooftop monitoring station data, whilst exposure overwhelmingly occurs at street level. In this study the relationship between street level and roof level grass pollen concentrations was investigated for city centre street canyon environments in Aarhus, Denmark, and London, UK, during the grass pollen seasons of 2010 and 2011 respectively. For the period mid-day to late evening, street level concentrations in both cities tended to be lower than roof-level concentrations, though this difference was found to be statistically significant only in London. The ratio of street/roof level concentrations was compared with temperature, relative humidity, wind speed and direction, and solar radiation. Results indicated that the concentration ratio responds to wind direction with respect to relative canyon orientation and local source distribution. In the London study, an increase in relative humidity was linked to a significant decrease in street/roof level concentration ratio, and a possible causative mechanism involving moisture mediated pollen grain buoyancy is proposed. Relationships with the other weather variables were not found to be significant in either location. These results suggest a tendency for monitoring station data to overestimate exposure in the canyon environment.