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排序方式: 共有3899条查询结果,搜索用时 15 毫秒
991.
Chris Melvin Eifion Jewell Jakob Miedema Koen Lammers Arnoud de Vooys Andrew Allman Neil McMurray 《Packaging Technology and Science》2019,32(7):345-355
Tinplate surface morphology and chemistry is adjusted during the manufacturing process in order to meet the demands of its subsequent product use, the commonest being visual appearance and food packaging stability. A comprehensive experimental study on an industrial tinning line varied the surface roughness and the tin coating weight with the characterization through X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), white light interferometer (WLI), optical imaging, and lacquer adhesion measurement. Increasing tin weight lowers the adhesion through the production of a thicker disorganized tin oxide layer which has a greater tendency to fracture under shearing forces. There is no evidence that the substrate roughness improves the adhesion of the lacquer. Analysis of the failure location identifies fracture in the tin oxide layer below the passivation layer. The findings have impacts on the next generation of passivation materials for tinplate as it has been clearly demonstrated that growth in tin oxide thickness, particularly when unstructured, has a detrimental impact on lacquer adhesion. 相似文献
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Phoebe Louiseanne Heseltine Joseph Hosken Chris Agboh David Farrar Shervanthi Homer‐Vanniasinkam Mohan Edirisinghe 《大分子材料与工程》2019,304(1)
Silk has attracted considerable interest for use in biomedical applications due to its high strength and promising biocompatibility. Degummed silk, consisting only of silk fibroin (SF), has been processed using various methods and can be made into films, sponges, and fibers. Pressurized gyration (PG) is capable of rapidly producing aligned fibers and offers a great amount of control over their structure and morphology. Here, SF fibers are produced for the first time using PG. The effect of varying SF concentration and applied working pressure to the gyration vessel is reported, along with the resulting effect on fiber diameter, morphology, and structural composition. Aligned microfibers are found at concentrations of 8, 10, 12 w/v%, with the lowest fiber diameters reported at 8 w/v% SF 0.3 MPa applied pressure (2.1 ± 1.3 µm). Fourier‐transform infrared spectroscopy (FTIR) confirms the existence of PG spun fibers in both random coil and β‐sheet formations. 相似文献
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996.
Ioannis Ieropoulos Pavlina Theodosiou Benjamin Taylor John Greenman Chris Melhuish 《International Journal of Hydrogen Energy》2017,42(3):1783-1790
The microbial fuel cell (MFC) is an energy transducer that can directly produce electricity from bacterial oxidation of organic matter. MFCs consist of two reaction chambers (anode and cathode) separated by a semipermeable membrane. This study describes the work carried out towards the optimization of critical MFC components, with 3D fabricated materials. The response of the optimized fuel cells, which were fed with soft materials such as gelatin, alginate and Nafion?, is also reported. The optimised components were the membrane and the cathode electrode. A conventional Nafion membrane was substituted with a custom made terracotta sheet and the electrode used was a single sheet of carbon veil coated with an activated carbon paste. The results showed that among the soft materials tested within the anodic chamber, gelatin performed the best; it also revealed that even after a 10-day starvation period gelatin demonstrated better longevity. These results show that MFCs have the potential to be 3D-printed monolithically using the EVOBOT platform. 相似文献
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Vladimir Leonov Tom Torfs Ruud J. M. Vullers Chris Van Hoof 《Journal of Electronic Materials》2010,39(9):1674-1680
Hybrid wearable energy harvesters consisting of a thermoelectric generator (TEG) and photovoltaic (PV) cells are used in this
work for powering two autonomous medical devices: an electroencephalography (EEG) system and an electrocardiography (ECG)
system in a shirt. Two alternative solutions for powering the systems have been implemented. In the battery-free EEG diadem,
PV cells cover the outer surface of radiators used in a TEG. In the ECG shirt, thermoelectric modules are the main power supply
that constantly recharges a battery, while PV cells are used mainly to provide standby power, i.e., when the shirt is not
worn. Both devices are maintenance free for their entire service life. 相似文献
999.
Gene promoter DNA methylation patterns have a limited role in orchestrating transcriptional changes in the fetal liver in response to maternal folate depletion during pregnancy
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1000.
Chris Aldrich 《Chemical Engineering Communications》2000,177(1):121-137
Experimental results indicate that autoassociative neural networks provide a robust method for the identification of clusters in process data. Cluster identification is accomplished by extracting a single feature from each multivariate data vector. The ranked features can be used to construct a feature curve, which is subsequently used as a basis for partitioning of the data space. In three case studies, involving two sets of ore samples, and a set of flotation froth features, with 11, 13 and 5 variables respectively, the clusters identified with the neural network appeared to be better than those obtained by conventional means. 相似文献