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(searched for: doi:(10.22261/*))
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Published: 10 August 2020
Journal of Ecoacoustics; doi:10.22261/jea

The publisher has not yet granted permission to display this abstract.
Published: 9 October 2019
Veruscript Functional Nanomaterials; doi:10.22261/fnan

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Cambridge Journal of Eurasian Studies; doi:10.22261/cjes

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Published: 9 October 2019
Veruscript Functional Nanomaterials; doi:10.22261/au7wjr

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Journal of the Global Power and Propulsion Society; doi:10.22261/jgpps

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John Coull, Christopher Clark, Raul Vazquez
Journal of the Global Power and Propulsion Society, Volume 3; doi:10.22261/jgpps.oeymde

Abstract:
The development of hub and casing boundary layers through a turbomachine is difficult to predict, giving rise to uncertainty in the boundary conditions experienced by each blade row. Previous studies in turbine cascades disagree on the sensitivity of endwall loss to such inlet conditions. This paper explores the problem computationally, by examining a large number of turbine cascades and varying the inlet boundary layer thickness. It is demonstrated that the sensitivity of endwall loss to inlet conditions is design dependent, and determined by the component of endwall loss associated with the secondary flow. This Secondary-Flow-Induced loss is characterised by a vorticity factor based on classical secondary flow theory. Designs that produce high levels of secondary vorticity tend to generate more loss and are more sensitive to inlet conditions. This sensitivity is largely driven by the dissipation of Secondary Kinetic Energy (SKE): thickening the inlet boundary layer causes the secondary vorticity at the cascade exit to be more dispersed within the passage, resulting in larger secondary flow structures with higher SKE. The effects are captured using a simple streamfunction model based on classical secondary flow theory, which has potential for preliminary design and sensitivity assessment.
Scott J. Wilson, Erin M. Bayne
Published: 13 February 2019
Journal of Ecoacoustics, Volume 3, pp 1-1; doi:10.22261/jea.i4b2lf

Abstract:
The boreal forest of Alberta, Canada is important breeding habitat for North American songbirds. Thousands of oil and gas wellsites exist in this region that have been actively reclaimed since the 1960s. Limited information exists on how songbirds respond to regeneration of wellsites following reclamation. Methods that provide spatially accurate data are required to determine impacts of these small disturbances characteristic of energy sector on songbirds. Acoustic localization can be used to determine singing locations, based on time of arrival differences of songs to an array of microphones. We used acoustic localization to determine the assemblage of songbirds on 12 reclaimed wellsites ranging from 7 to 49 years since reclamation, and how the similarity of this assemblage to 12 control mature forest sites (greater than 80 years old) changed with increasing canopy cover on the wellsite. Songbird community composition became more similar to mature forest as canopy cover increased on reclaimed wellsites. Results from this study suggest that wellsite reclamation practices are allowing for initial suitable vegetation recovery, however more research on the effectiveness of different strategies at promoting regeneration of wellsites and subsequent impact on songbird communities is required.
Robert Pearce, Peter Ireland, Edwin Dane
Journal of the Global Power and Propulsion Society, Volume 3; doi:10.22261/jgpps.wlal1f

Abstract:
Accurate analysis of the performance of a turbine blade cooling system is essential to allow the blade life to be safely predicted. The latter is essential as the business model for an engine can be strongly dependent on the duration between engine shop visits. Some recent heat transfer research has focused on increasing heat transfer levels in order to reduce turbine blade metal temperatures, however for engine designers it is the life of the blade, determined in part by the stress levels within it, that are of main concern. This paper uses heat transfer and stress analysis within the same software environment to examine the influence of the HTC levels in different regions of an engine representative leading edge impingement cooling system on both metal temperature and stress levels. The results of these analyses are then combined to show that, with attention to cooling in different regions of the blade, reductions in stress levels of 6% can be achieved in the most highly stressed regions of the blade with achievable alterations in heat transfer levels.
Sciprofile linkKamrul Hossain, Yue Xu, Li Lifan
Published: 25 January 2019
Cambridge Journal of Eurasian Studies, Volume 3, pp 1-15; doi:10.22261/cjes.f3osgp

Abstract:
In recent years, China has evidently become a significant actor in the Arctic – a region located around the circumpolar north comprising territories of eight states and the Arctic Ocean. In 2013, China’s achievement of observer status at the Arctic Council – the high level inter-governmental forum of these eight circumpolar states – provided the country with legitimacy in its growing engagement with the Arctic region and its actors. A number of interests in the region motivates this engagement, most crucially that the Arctic is a resource rich region full of potential to further boost China’s local economy. The region contains, among other resources, approximately one-fourth of world’s undiscovered oil and gas resources. The increased melting of sea ice in the Arctic Ocean as a result of global warming is gradually opening access to water routes, and the region itself. The Arctic sea routes, in particular the Northern Sea Route (NSR), have already been identified as crucial navigation routes for China to expand its Belt and Road Initiative (BRI) to the Arctic. The expansion is now widely known as the Silk Road on the Ice or the Polar Silk Road wherein China closely cooperates with Russia and other Arctic states to promote the infrastructural development to operationalise the NSR. China’s investments in a number of projects are making the country an influential actor in the Arctic region. As such, China’s Arctic engagement is at times perceived as an attempt to enhance its ambitions, not only in terms of its economic interests, but also to move a step further towards gaining great power status in world politics. While China firmly commits to respect the sensitive environmental considerations existing in the Arctic and the sovereignty of the Arctic states, it also explicitly highlights its legitimate rights under international law, i.e., freedom of navigation through the Arctic sea routes. In this context, the following article explores the extension of China’s Silk Road Economic Belt to the Arctic vis-á-vis the possible geopolitical dynamics, and whether China’s increasing engagement in the Arctic accelerates its political ambition to expand its great power status.
Sciprofile linkRaghvendra Kumar Mishra, Anuj Kumar Chhalodia, Santosh K. Tiwari, Vadym Mochalin, Vincent Pichot, Robert Bogdanowicz, Huan-Cheng Chang, Qing Huang, Andreas Schell, Masfer Alkahtani
Published: 19 December 2018
Veruscript Functional Nanomaterials, Volume 2, pp 1-23; doi:10.22261/8w2eg0

Abstract:
From ancient times, diamond has been a highly praised ornamental object. This version of carbon exhibits outstanding properties, such as chemical inertness, high thermal stability, exceptional hardness and very good luminescence. These properties can be enhanced and utilized for many applications if the nanoform of bulk diamond is considered. Thus, by taking advantage of these types of features, the surfaces of nanodiamonds can be engineered for desired applications. For example, incorporating active functional groups on the surface and tuning electrostatic characteristics makes nanodiamonds a viable colloid in a variety of solvents, increases adsorption behaviour, helps utilization of photonic crystals and creates compatibility with biomolecules and many polymers. It has been found that optical properties in nanodiamonds, due to the luminescent colour centres, depends on the proximity of their surface properties. Therefore, to modify the surface of nanodiamonds for a specific application, a fundamental knowledge of natural science and engineering is essential. Most nanodiamonds and their derivatives are produced via detonation method and it is understood that their structure is affected by the synthesis protocols and successive processing steps. In this review, the present status and prospects for nanodiamonds in contest of synthesis techniques, structural properties, stability, electronics, tribology and lubrication properties has been explored.
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