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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The removal of smokes and mists

Guthrie, David Alan January 1955 (has links)
A colorimetric quantitative analysis for di-n-octylphthalate and other aromatic esters has been developed which is capable of determining as little as 0.1 milligrams of an ester. This method is based on the formation of hydroxamic acid from esters using hydroxylamine hydrochloride in an alkaline medium. On the addition of an acidified solution of ferric per-chlorate, a red-colored complex of ferric hydroxamate is formed, proportionate in intensity to the weight of ester present. Mist composed of di-n-octylphalate droplets of 0.869 microns average diameter was removed from air at substantially atmospheric temperature and pressure by passing the air up through a bed of 150/200 mesh silica gel fluidized in a 2-1/4 inch glass column. Removal efficiency, defined as the percent (by weight) removal of the mist was substantially independent of the entering concentration over the range 0.765 to 0.965 milligrams of ester per cubic foot of air. For a given bed, removal efficiency improved with decreasing superficial gas velocity. Two bed weights were used, 13.25 grams per square centimeter and 25.35 grams per square centimeter, and it was found that the removal efficiency was practically in dependent of the bed weights. The maximum removal efficiency was 88.8% at a superficial bed velocity of 3.2 centimeters per second and a bed weight of 13.25 grams per square centimeter. The same mist was removed by passing the gas stream through various venturi nozzles with ports in the throat through which fine silica gel (150/200 mesh) entered by gravity and aspiration into the gas stream. For the venturi nozzles the removal efficiency generally increased with increasing velocities; however, the maximum removal efficiency obtained was only about 40%. It is shown that the behavior and collection efficiences obtained with the two devices can be satisfactorily explained if the fluidized bed is assumed to collect the aerosol particles by diffusional processes only, and the venturi tube, by inertial processes only, at least for aerosol particles of the size used in this work. The problem of efficient removal of aerosol particles in the range of 0.1 to 1.0 microns diameter has still not been solved in an economical manner for many cases of industrial importance. The removal becomes even more difficult when the aerosol particles are fairly uniform in size. The purpose of the present work was to conduct a preliminary testing of new devices which might be more efficient for small particles than those now commonly used. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
12

Removal and leakage of environmental tobacco smoke from model smoking room /

Chan, Tsz Tung. January 2009 (has links)
Includes bibliographical references (p. 90-100).
13

Environmental tobacco smoke and wellbeing

Nanwani, Shalini Suresh. January 2003 (has links)
Thesis (M.Med.Sc.)--University of Hong Kong, 2003. / Includes bibliographical references (leaves 53-60). Also available in print.
14

Aerosol characterization for agricultural field burning smoke

Jimenez, Jorge Rodrigo, January 2006 (has links) (PDF)
Thesis (Ph. D. in civil engineering)--Washington State University, December 2006. / Includes bibliographical references.
15

University Students’ Perceptions and Behaviors Regarding Secondhand Smoke, Smoking Bans, and Spending in Smoke-Free Establishments

Molloy, Brigid A. 28 September 2005 (has links)
No description available.
16

Responsibility and resistance : children and young people's accounts of smoking in the home and car

Rowa-Dewar, Neneh January 2013 (has links)
Following the implementation of the smokefree law in 2006, which formed part of the Smoking, Health and Social Care (Scotland) Act 2005, smoking in enclosed public spaces has been prohibited in Scotland. The law has led to a number of improvements in public health but does not cover homes and cars where children are primarily exposed. Secondhand smoke (SHS) exposure is associated with particularly significant risks to child health, yet few studies have explored children’s perspectives on SHS and smoking in the home and car. Comprising a qualitative exploration of the views and experiences of 38, 10- to 15-year-olds of SHS in the home and car, this thesis begins to address this gap. It addresses the nature and extent of children’s involvement in negotiating smoking restrictions, compares the understandings, experiences and involvement among participants living in communities of contrasting socioeconomic profiles and considers the implications for health promotion interventions aimed at reducing children’s exposure to SHS in the home and car. Informed by a Childhood Studies perspective, the study focuses, both in methods and content, on the voices and agency of the participants. Recruited from two Edinburgh communities with contrasting socioeconomic profiles, the participants were interviewed either individually, in pairs or in small focus groups about their understandings of SHS, smoking restrictions in their homes and cars and their role in negotiating them. Home floor plans constructed by the participants were used to prompt discussion and also served to identify spatial and temporal home smoking restrictions. Both discursive and thematic techniques were used in analysis. The thesis details the participants’ overt and covert strategies to resist family members’ smoking, demonstrating the active roles that participants describe in their accounts. While acknowledging SHS as a health risk and using an embodied language of disgust to describe it, the participants’ main concern was for their smoking family members’ health, rather than their own. Many participants also challenged the stigma surrounding smoking parents by detailing the ways in which their parents restricted where, how much and with whom they smoked. Parents were described as especially careful in protecting small children from SHS. While most participants described such protective practices, those from the disadvantaged area reported less stringent smoking restrictions that were more challenging to negotiate. Participants’ resistant (to smoking) and defensive (of parents who smoke) accounts may stem from the growing stigma associated with smoking, particularly smoking in the presence of children. Such findings highlight the importance of a sensitive and asset based public health response that acknowledges parents’ attempts to protect their children from SHS and recognises the potential of the active role of children in family negotiations around smoking in the home and car.
17

Evidence-based practice guidelines: nurses' interventions for care-takers of paediatric in-patients to reducechildren's environmental tobacco smoke exposure

唐海寧, Tong, Hoi-ning, Mandy. January 2009 (has links)
published_or_final_version / Nursing Studies / Master / Master of Nursing
18

The Efficiency of Plastic Skylight Panels as Smoke Vents in the Event of Fire

Gaskin, Jeremy Mervyn January 2010 (has links)
Concerns have been raised over the use of plastic skylights as smoke vents in large single story buildings. The plastic skylights provide natural light to the building. There has been an assumption that these plastic panels will melt and provide smoke and heat venting during a fire. The plastics commonly used in New Zealand, polyvinyl chloride (PVC), polycarbonate, acrylic and glass fibre-reinforced polyester (GRP) have been tested in small scale experiments to further the understanding of the behaviour of the materials at elevated temperatures. The behaviour of particular interest is the effectiveness of the skylight as a vent for hot buoyant gases. Small scale experiments have been conducted to find the mass flow rate of an unobstructed vent. Experiments have then been carried out on samples of the four skylight materials for a range of exposure temperatures and times. The mass flow has been measured for the deformed sample and compared to the unobstructed flow. The results of the small scale experiments have been analysed and an empirical relationship has been developed for the PVC and polycarbonate material. The acrylic behaviour does not provide enough data to include it in the empirical relationship. The GRP failed to melt and was therefore also excluded from the empirical relationship. A model has been developed to demonstrate the use of the empirical relationship. The model compares four cases, the vents always open, the vents always closed, the vents opening at a single value and the area when calculated using the empirical relationship.
19

Smoke Management and Egress Design Analysis of High Rise Buildings

Qiu, Wen-Yu 27 June 2000 (has links)
None
20

Evidence-based practice guidelines nurses' interventions for care-takers of paediatric in-patients to reduce children's environmental tobacco smoke exposure /

Tong, Hoi-ning, Mandy. January 2009 (has links)
Thesis (M. Nurs.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 34-36).

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