188 research outputs found
Investigation into high-temperature corrosion in a large-scale municipal waste-to-energy plant
High-temperature corrosion in the superheater of a large-scale waste-to-energy plant was investigated. A comparison of nickel-/iron-based alloys and austenitic stainless steel probes placed in the furnace demonstrated that temperature and particle deposition greatly influence corrosion. Nickel-based alloys performed better than the other metal alloys, though an aluminide coating further increased their corrosion resistance. Sacrificial baffles provided additional room for deposit accumulation, resulting in vigorous deposit-induced corrosion. Computational modelling (FLUENT code) was used to simulate flow characteristics and heat transfer. This study has shown that the use of aluminide coatings is a promising technique for minimising superheater corrosion in such facilities. (C) 2010 Elsevier Ltd. All rights reserved
On-chip Terahertz Spectroscopy of Liquid Mixtures
We demonstrate 'through-substrate' sensing of fluids for application in the terahertz spectroscopy of biological materials. This technique employs planar Goubau lines with integrated photoconductive material, formed on a flexible, thin polyimide substrate, and bonded to a microfluidic channel. Few-picosecond pulses are used to probe liquid samples confined within the channel, over a total interaction length of 4 mm, overcoming water-absorption limitations of free-space terahertz transmission measurements
Compressed gas domestic aerosol valve design using high viscous product
Most of the current universal consumer aerosol products using high
viscous product such as cooking oil, antiperspirants, hair removal cream
are primarily used LPG (Liquefied Petroleum Gas) propellant which is
unfriendly environmental. The advantages of the new innovative
technology described in this paper are:
i. No butane or other liquefied hydrocarbon gas is used as a propellant
and it replaced with Compressed air, nitrogen or other safe gas
propellant.
ii. Customer acceptable spray quality and consistency during can lifetime
iii. Conventional cans and filling technology
There is only a feasible energy source which is inert gas (i.e.
compressed air) to replace VOCs (Volatile Organic Compounds) and
greenhouse gases, which must be avoided, to improve atomisation by
generating gas bubbles and turbulence inside the atomiser insert and the
actuator. This research concentrates on using “bubbly flow” in the valve
stem, with injection of compressed gas into the passing flow, thus also
generating turbulence.
The new valve designed in this investigation using inert gases has
advantageous over conventional valve with butane propellant using high
viscous product (> 400 Cp) because, when the valving arrangement is
fully open, there are negligible energy losses as fluid passes through the
valve from the interior of the container to the actuator insert. The use of
valving arrangement thus permits all pressure drops to be controlled,
resulting in improved control of atomising efficiency and flow rate,
whereas in conventional valves a significant pressure drops occurs
through the valve which has a complex effect on the corresponding
spray
Predictors of recruitment and retention in randomized controlled trials of behavioural smoking cessation interventions: a systematic review and meta-regression analysis
AIM: To investigate predictors of participant eligibility, recruitment, and retention in behavioural randomised controlled trials (RCTs) for smoking cessation. METHOD: Systematic review and pre-specified meta-regression analysis of behavioural RCTs for smoking cessation including adult (≥18 years old) smokers. The pre-specified predictors were identified through a literature review and experts' consultation and included participant, trial and intervention characteristics and recruitment and retention strategies. Measurements included eligibility rates (proportion of people eligible for the trials), recruitment rates, retention rates, and differential retention rates. RESULTS: 172 RCTs with 89,639 participants. Eligibility [median 57.6%; IQR 34.7-83.7], recruitment [median 66.4%; IQR 42.7-85.2] and retention rates [median 80.5%; IQR 42.7-85.2] varied considerably across studies. For eligibility rates, the recruitment strategy appeared not to be associated with eligibility rates. For recruitment rates, use of indirect recruitment strategies (e.g., public announcements) [OR 0.30, 95% CI 0.11-0.82] and self-help interventions [OR 0.14, 95% CI 0.03-0.67] were associated with lower recruitment rates. For retention rates, higher retention was seen if the sample had ongoing physical health condition/s [OR 1.66, 95% CI 1.04-2.63] whereas lower retention was seen amongst primarily female samples [OR 0.83, 95% CI 0.71-0.98] and those motivated to quit smoking [OR 0.74, 95% CI 0.55-0.99], when indirect recruitment methods were used [OR 0.60, 95% CI 0.38-0.97], and at longer follow-up assessments [OR 0.83, 95% CI 0.79-0.87]. For differential retention, higher retention in the intervention group occurred when the intervention but not comparator group received financial incentives for smoking cessation [OR 1.35, 95% CI: 1.02-1.77]. CONCLUSIONS: In randomised controlled trials of behavioural smoking cessation interventions, recruitment and retention rates appear to be higher for smoking cessation interventions that include a person-to-person rather than at-a-distance contact; male participants, smokers with chronic conditions, smokers not initially motivated to quit and shorter follow-up assessments seems to be associated with improved retention; financial incentive interventions improve retention in groups receiving them relative to comparison groups
Investigation into free-space terahertz radiation from a LT-GaAs-on-quartz photoconductive emitter
We report on large-area photoconductive THz emitters and detectors with an LT-GaAs active region fabricated on quartz substrates using a lift-off transfer process. These devices are compared to the same LT-GaAs emitters when fabricated on the growth substrate. We find that the transferred devices show higher optical-to-THz conversion efficiencies and significantly larger breakdown fields
CO₂ gasification of bio-char derived from conventional and microwave pyrolysis
Thermal-chemical processing of biomass is expected to provide renewable and clean energy and fuels in the future. Due to the nature of endothermic reactions, microwave and conventional heating have been applied to this technology. However, more studies need to be carried out to clarify the difference between these two heating technologies. In this work, we investigated two bio-char samples produced from conventional pyrolysis of wood biomass (yield of bio-char: 38.48 and 59.70 wt.%, respectively) and one bio-char produced from microwave pyrolysis with a yield of 45.16 wt.% from the same biomass sample at different process conditions. Various methodologies have been used to characterise the bio-chars. CO₂ gasification of bio-char has also been studied using a thermogravimetric analyser (TGA) and a fixed-bed reaction system. The results show that volatile and carbon contents of the bio-char derived from microwave pyrolysis were between the two conventional bio-chars. However, the microwave bio-char is more reactive for CO₂ gasification, as more CO was released during TGA experiments, and the CO release peak was narrower compared with the CO₂ gasification of the conventional bio-chars. It is suggested that the conventional bio-char is less reactive due to the presence of more secondary chars which are produced from secondary reactions of volatiles during the conventional biomass pyrolysis. While the microwave pyrolysis generates more uniform bio-chars with less secondary char, and therefore, has advantages of producing bio-char for downstream char gasification
Tailoring CONSORT-SPI to improve the reporting of smoking cessation intervention trials: An expert consensus study
BACKGROUND AND AIMS: Inadequate reporting of smoking cessation intervention trials is common and leads to significant challenges for researchers. The aim of this study was to tailor CONSORT (Consolidated Standards of Reporting Trials)-SPI (Social and Psychological Interventions) guidelines to improve reporting of trials of behavioural interventions to promote smoking cessation. METHOD: Informed by missing data from the IC-SMOKE (Intervention and Comparison group support provided in SMOKing cEssation) systematic review project, this study used a multi-stage Delphi process to examine which items could be added or modified to improve the reporting of smoking cessation trials. The first stage involved an on-line survey of 17 international experts in smoking cessation and trial methodology voting on the importance of items for inclusion in the updated guidelines. This was followed by a face-to-face expert consensus meeting attended by 15 of these experts, where the final inclusion and exclusion of new items and modifications were agreed upon. A nine-point Likert scale was used to establish consensus, with suggested modifications requiring agreement of 75% or more. Disagreements in the first stage were presented again at the second stage for discussion and a second round of voting. Only items which reached the threshold for agreement were included. RESULTS: The experts agreed on the inclusion of 10 new items and the specification of 12 existing items. This included modifications that could apply to trials more widely (e.g. the rationale for the comparator), but also modifications that were very specific to smoking cessation trials (e.g. the reporting of smoking cessation outcomes). CONCLUSIONS: A Delphi study has developed a modified CONSORT-SPI guideline (CONSORT-SPI-SMOKE) to improve the reporting of trials of behavioural interventions to promote smoking cessation
Tailoring CONSORT-SPI to Improve the Reporting of Smoking Cessation Intervention Trials : An expert consensus study
Primary funding: This work was funded by Cancer Research UK (application number C50862/A25405). The funder has no role in protocol design, decision to publish or preparation of the manuscript.Peer reviewedPublisher PD
Persistent Leatherback Turtle Migrations Present Opportunities for Conservation
Effective transboundary conservation of highly migratory marine animals requires international management cooperation as well as clear scientific information about habitat use by these species. Populations of leatherback turtles (Dermochelys coriacea) in the eastern Pacific have declined by >90% during the past two decades, primarily due to unsustainable egg harvest and fisheries bycatch mortality. While research and conservation efforts on nesting beaches are ongoing, relatively little is known about this population of leatherbacks' oceanic habitat use and migration pathways. We present the largest multi-year (2004–2005, 2005–2006, and 2007) satellite tracking dataset (12,095 cumulative satellite tracking days) collected for leatherback turtles. Forty-six females were electronically tagged during three field seasons at Playa Grande, Costa Rica, the largest extant nesting colony in the eastern Pacific. After completing nesting, the turtles headed southward, traversing the dynamic equatorial currents with rapid, directed movements. In contrast to the highly varied dispersal patterns seen in many other sea turtle populations, leatherbacks from Playa Grande traveled within a persistent migration corridor from Costa Rica, past the equator, and into the South Pacific Gyre, a vast, low-energy, low-productivity region. We describe the predictable effects of ocean currents on a leatherback migration corridor and characterize long-distance movements by the turtles in the eastern South Pacific. These data from high seas habitats will also elucidate potential areas for mitigating fisheries bycatch interactions. These findings directly inform existing multinational conservation frameworks and provide immediate regions in the migration corridor where conservation can be implemented. We identify high seas locations for focusing future conservation efforts within the leatherback dispersal zone in the South Pacific Gyre
Tailoring CONSORT-SPI to improve the reporting of smoking cessation intervention trials: An expert consensus study
Background and Aims: Inadequate reporting of smoking cessation intervention trials is common and leads to significant challenges for researchers. The aim of this study was to tailor CONSORT (Consolidated Standards of Reporting Trials)-SPI (Social and Psychological Interventions) guidelines to improve reporting of trials of behavioural interventions to promote smoking cessation. Method: Informed by missing data from the IC-SMOKE (Intervention and Comparison group support provided in SMOKing cEssation) systematic review project, this study used a multi-stage Delphi process to examine which items could be added or modified to improve the reporting of smoking cessation trials. The first stage involved an on-line survey of 17 international experts in smoking cessation and trial methodology voting on the importance of items for inclusion in the updated guidelines. This was followed by a face-to-face expert consensus meeting attended by 15 of these experts, where the final inclusion and exclusion of new items and modifications were agreed upon. A nine-point Likert scale was used to establish consensus, with suggested modifications requiring agreement of 75% or more. Disagreements in the first stage were presented again at the second stage for discussion and a second round of voting. Only items which reached the threshold for agreement were included. Results: The experts agreed on the inclusion of 10 new items and the specification of 12 existing items. This included modifications that could apply to trials more widely (e.g. the rationale for the comparator), but also modifications that were very specific to smoking cessation trials (e.g. the reporting of smoking cessation outcomes). Conclusions: A Delphi study has developed a modified CONSORT-SPI guideline (CONSORT-SPI-SMOKE) to improve the reporting of trials of behavioural interventions to promote smoking cessation
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