Development of a nano-heat transfer fluid carrying direct absorbing receiver for concentrating solar collectors
INTERNATIONAL JOURNAL OF LOW-CARBON TECHNOLOGIES
Authors: Toppin-Hector, Ashley; Singh, Harjit
Abstract
A MATLAB-based computer model to design a novel directly absorbing receiver system (DARS) for concentrating solar collectors employing nanofluid-based solar radiation volumetric absorption is presented. Graphene and aluminum nanosphere-based suspensions in Therminol VP-1 were simulated to identify the optimum thermo-geometric configuration of a DARS comprising a transparent all glass tubular absorber. Several particle concentrations were simulated scrutinizing the optical response of the two colloidal dispersions to yield a minimum supply temperature of 250 degrees C; further investigated are the implications of fluid flow velocity upon system yield. The resulting temperature fields and geometric dimensions of the DARS are predicted. Findings demonstrate that the DARS is able to deliver heat at similar to 265 degrees C with a receiver tube diameter of 5 mm opposed to commercially available 70-mm diameter metallic absorbers.
Swallowing outcomes following Intensity Modulated Radiation Therapy (IMRT) for head & neck cancer - A systematic review
ORAL ONCOLOGY
Authors: Roe, Justin W. G.; Carding, Paul N.; Dwivedi, Raghav C.; Kazi, Rehan A.; Rhys-Evans, Peter H.; Harrington, Kevin J.; Nutting, Christopher M.
Abstract
Purpose: A systematic review to establish what evidence is available for swallowing outcomes following IMRT for head and neck cancer. Methods: Online electronic databases were searched to identify papers published in English from January 1998 to December 2009. Papers were independently appraised by two reviewers for methodological quality, method of swallowing evaluation and categorized according to the World Health Organisation's International Classification of Health Functions. The impact of radiation dose to dysphagia aspiration risk structures (DARS) was also evaluated. Results: Sixteen papers met the inclusion criteria. The literature suggests that limiting the radiation dose to certain structures may result in favourable swallowing outcomes. Methodological limitations included variable assessment methods and outcome measures and heterogeneity of patients. There are only limited prospective data, especially where pre-treatment measures have been taken and compared to serial post-treatment assessment. Conclusions: Few studies have investigated the impact of IMRT on swallow function and the impact on everyday life. Initial studies have reported potential benefits but are limited in terms of study design and outcome data. Further well designed, prospective, longitudinal swallowing studies including multidimensional evaluation methods are required to enable a more comprehensive understanding of dysphagia complications and inform pre-treatment counselling and rehabilitation planning. (C) 2010 Elsevier Ltd. All rights reserved.