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91.
Abstract This paper summarises skating regulation around Australia, focusing on Tasmania. Such analysis is timely; the Australian Road Rules adopted in December 1999 expand skating from recreation to a mode of transport whose legitimacy assumes access to roads and footpaths, and deploys complex politics of identity and space, citizenship and access, and mobility. 相似文献
92.
93.
Oran ES Williams FA 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2012,370(1960):534-543
The motivation for devoting a Theme Issue to explosions is discussed. As subsequent articles in the issue are written with the assumption that the reader has had a certain amount of previous exposure to the subject, some of the history and necessary background information are presented here. The topics on explosions that will be encountered in the remaining articles are previewed. Finally, several important future outstanding research problems, beyond those addressed in the following articles, are discussed, with the objective of complementing the coverage of explosions in this issue. 相似文献
94.
95.
Sands CJ Coen M Ebbels TM Holmes E Lindon JC Nicholson JK 《Analytical chemistry》2011,83(6):2075-2082
Statistical total correlation spectroscopy (STOCSY) is a well-established and valuable method in the elucidation of both inter- and intrametabolite correlations in NMR metabonomic data sets. Here, the STOCSY approach is extended in a novel Iterative-STOCSY (I-STOCSY) tool in which correlations are calculated initially from a driver peak of interest and subsequently for all peaks identified as correlating with a correlation coefficient greater than a set threshold. Consequently, in a single automated run, the majority of information contained in multiple STOCSY calculations from all peaks recursively correlated to the original user defined driver peak of interest are recovered. In addition, highly correlating peaks are clustered into putative structurally related sets, and the results are presented in a fully interactive plot where each set is represented by a node; node-to-node connections are plotted alongside corresponding spectral data colored by the strength of connection, thus allowing the intuitive exploration of both inter- and intrametabolite connections. The I-STOCSY approach has been here applied to a (1)H NMR data set of 24 h postdose aqueous liver extracts from rats treated with the model hepatotoxin galactosamine and has been shown both to recover the previously deduced major metabolic effects of treatment and to generate new hypotheses even on this well-studied model system. I-STOCSY, thus, represents a significant advance in correlation based analysis and visualization, providing insight into inter- and intrametabolite relationships following metabolic perturbations. 相似文献
96.
97.
Carbon composites containing novolac/furfuryl alcohol resins with hexamethylene tetramine (HMTA) as a crosslinker and carbon black or mesophase pitch as an additive, were heated to 1000 °C under Argon atmosphere. Carbonization chemistry was studied including the nitrogen-containing structures in the final carbons. The volatiles released during the heating were furfuryl, phenol-benzene species, methane, ethane and other small molecular species such as moisture, CO2, CO and ammonia. When carbon black was used as an additive in the composite, a considerable amount of furfuryl and phenolic species were “trapped” on the surface of carbon black particles, resulting in a higher carbon yield. Certain carbonization reactions also occurred at lower temperatures, and the dimensional shrinkage was reduced as compared to the resin-only system. On the other hand, the mesophase pitch additive formed homogeneous morphologies with the resin binder, participated in the carbonization process of the resin binder and formed amorphous carbons with porous structures and dimensional expansion. Manipulating the composition and variety of the additives could produce carbon composites with designed performance. 相似文献
98.
Fonville JM Carter C Cloarec O Nicholson JK Lindon JC Bunch J Holmes E 《Analytical chemistry》2012,84(3):1310-1319
Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) provides localized information about the molecular content of a tissue sample. To derive reliable conclusions from MSI data, it is necessary to implement appropriate processing steps in order to compare peak intensities across the different pixels comprising the image. Here, we review commonly used normalization methods, and propose a rational data processing strategy, for robust evaluation and modeling of MSI data. The approach includes newly developed heuristic methods for selecting biologically relevant peaks and pixels to reduce the size of a data set and remove the influence of the applied MALDI matrix. The methods are demonstrated on a MALDI MSI data set of a sagittal section of rat brain (4750 bins, m/z = 50-1000, 111 × 185 pixels) and the proposed preferred normalization method uses the median intensity of selected peaks, which were determined to be independent of the MALDI matrix. This was found to effectively compensate for a range of known limitations associated with the MALDI process and irregularities in MS image sampling routines. This new approach is relevant for processing of all MALDI MSI data sets, and thus likely to have impact in biomarker profiling, preclinical drug distribution studies, and studies addressing underlying molecular mechanisms of tissue pathology. 相似文献
99.
100.
Vertical nanowire array-based light emitting diodes 总被引:4,自引:0,他引:4
Electroluminescence from a nanowire array-based light emitting diode is reported. The junction consists of a p-type GaN thin
film grown by metal organic chemical vapor deposition (MOCVD) and a vertical n-type ZnO nanowire array grown epitaxially from
the thin film through a simple low temperature solution method. The fabricated devices exhibit diode like current voltage
behavior. Electroluminescence is visible to the human eye at a forward bias of 10 V and spectroscopy reveals that emission
is dominated by acceptor to band transitions in the p-GaN thin film. It is suggested that the vertical nanowire architecture
of the device leads to waveguided emission from the thin film through the nanowire array. 相似文献