7 research outputs found
Biodegradable Cellulose Film Prepared from Banana Pseudo-Stem Using an Ionic Liquid for Mango Preservation
Get PDFThe excessive use and disposal of plastic packaging materials have drawn increasing concerns from the society because of the detrimental effect on environment and ecosystems. As the most widely used fruit packing material, polyethylene (PE) film is not suitable for long-term preservation of some tropical fruits, such as mangos, due to its inferior gas permeability. Cellulose based film can be made from renewable resources and is biodegradable and environmental-friendly, which makes it a promising alternative to PE as a packaging material. In this study, cellulose film synthesized from delignified banana stem fibers via an ionic liquid 1-Allyl-3-methylimidazolium chloride ([AMIm][Cl]) were evaluated as packing material for mangos preservation. The moisture vapor transmission rate and gas transmission rate of the synthesized cellulose film were 1,969.1 g/(m2⋅24 h) and 10,015.4 ml/(m2⋅24 h), respectively, which are significantly higher than those of commercial PE films. The high permeability is beneficial to the release of ethylene so that contribute to extend fruit ripening period. As a result, cellulose film packaging significantly decreased the disease and color indexes of mangos, while prolonged the storage and shelf life of marketable fruits. In addition, the cellulose film was decomposed in soils in 4 weeks, indicating an excellent biodegradability as compared to the PE plastic film
Poly Aryl Ether Ketones (PAEKs) and carbon-reinforced PAEK powders for laser sintering
Get PDFThis is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.This paper discusses various methods of fabrication of plain and carbon-reinforced composite powders, as well as a range of powder characterisation test methods suitable for defining powders for laser sintering. Two milling processes (based on disc blades and rotatory cutting knives) were used as methods of fabrication of powders, starting from injection moulding granule grades, for comparison with current powders obtained directly from polymerisation processes. It was found that the milling process affects the particles properties. The rotary milling produced powders with superior properties in comparison with the disc milling method. Tests including particle size distribution, angle of repose, aspect ratio, sphericity and roundness of particles were employed to compare and assess the suitability of powders for laser sintering. The Brunauer–Emmett–Teller test was identified as a useful method to define surface roughness and porosity of the particles. The carbon fibre (Cf) Poly Ether Ketone (PEK) granules milled well and after an additional sieving process created a good quality powder. This is the first attempt to investigate properties of PEK powder with encapsulated Cf and follow their sintering profile through hot-stage microscopy. It is expected that this type of composite powder will create isotropic structures in comparison with the highly anisotropic properties given by the known dry mix composite powders, currently used in laser sintering.© The Author(s) 2017
Open Access
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made
Enhanced Ductility of PEEK thin film with self-assembled fibre-like crystals
No full textThis is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Poly Ether Ether Ketone (PEEK) is a high temperature polymer material known for its
excellent chemical resistance, high strength and toughness. As a semi-crystalline polymer,
PEEK can become very brittle during long crystallisation times and temperatures helped as
well by its high content of rigid benzene rings within its chemical structure. This paper
presents a simple quench crystallization method for preparation of PEEK thin films with the
formation of a novel fibre-like crystal structure on the surface of the films. These quenched
crystallised films show higher elongation at break when compared with conventional melt
crystallised thin films incorporating spherulitic crystals, while the tensile strength of both
types of films (quenched crystallised and conventional melt) remained the same. The
fracture analysis carried out using microscopy revealed an interesting microstructure which
evolves as a function of annealing time. Based on these results, a crystal growth mechanism
describing the development of the fibre-like crystals on the surface of the quenched
crystallised films is proposed.This work is supported by the UK Engineering and Physical Science Research Council (EPSRC
Grant No EP/L017318/1-Particle Shape and Flow behaviour in Laser Sintering: from
modelling to experimental validation)
Imperial Competition Algorithm Improvement Considering Surgical Scheduling
Get PDFTo address the lack of resources for doctors, nurses and operating rooms when scheduling surgery, a hybrid imperial competition algorithm considering the surgery scheduling problem is proposed based on setting assumptions and using the idea of crossover operations in genetic algorithms
Information quality in proteomics
No full textProteomics, the study of the protein complement of a biological system, is generating increasing quantities of data from rapidly developing technologies employed in a variety of different experimental workflows. Experimental processes, e.g. for comparative 2D gel studies or LC-MS/MS analyses of complex protein mixtures, involve a number of steps: from experimental design, through wet and dry lab operations, to publication of data in repositories and finally to data annotation and maintenance. The presence of inaccuracies throughout the processing pipeline, however, results in data that can be untrustworthy, thus offsetting the benefits of high-throughput technology. While researchers and practitioners are generally aware of some of the information quality issues associated with public proteomics data, there are few accepted criteria and guidelines for dealing with them. In this article, we highlight factors that impact on the quality of experimental data and review current approaches to information quality management in proteomics. Data quality issues are considered throughout the lifecycle of a proteomics experiment, from experiment design and technique selection, through data analysis, to archiving and sharing. © The Author 2008. Published by Oxford University Press
Improved Hydrogen Release from Ammonia Borane Confined in Microporous Carbon with Narrow Pore Size Distribution
Get PDFThis is the author accepted manuscript. The final version is available from Royal Society of Chemistry via the DOI in this record.Ammonia borane is a promising hydrogen storage candidate due to its high hydrogen capacity and good stability at room temperature, but there are still some barriers to be overcome before it can be used for practical applications. We present the hydrogen release from ammonia borane confined in templated microporous carbon with extremely narrow pore size distribution. Compared with neat ammonia borane, hydrogen release temperature of ammonia borane confined in microporous carbon with pore size of 1.05 nm is significantly reduced, starting at 50 C and with peak dehydrogenation temperature centred at 86 C. The dehydrogenation kinetics of ammonia borane confined in templated microporous carbon is significantly improved and by-products including ammonia and diborane are also completely prohibited without any catalysts involved. The remarkable fast hydrogen release rate and high hydrogen storage capacity from ammonia borane confined in microporous carbon is due to the dramatic decrease in the activation energy of ammonia borane. This is so far the best performance among porous carbon materials used as the confinement scaffolds for ammonia borane in hydrogen storage, making AB confined in microporous carbon a very promising candidate for hydrogen storage.The financial support by the Royal Society and University of Exeter is greatly acknowledged
