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A method for the rapid, simultaneous determination of protein, fat, carbohydrate, non-protein nitrogen and total solids in milk and liquid dairy products by infrared reflectance spectroscopy is presented. The method is calibrated against known standards obtained by conventional, time-consuming wet chemical methods but, once calibrated, can be operated routinely by non-skilled personnel. The method is sensitive and accurate down to 0·5% w/v and can be applied to most liquid samples without any need for prior preparation. 相似文献
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Computer science often faces the criticism that it isn't actual science. Doing science means using the scientific method, which includes reporting results so that others can repeat and verify them. The problem with the computer science community is the lack of shared terms with precise semantics. When a researcher reports phenomenal results that can't be replicated, the author might be viewed as a brilliant alchemist, but such works undermine claims of being "science." 相似文献
14.
Charles A. White John F. Kennedy Anna Lombard Valeria Rossetti 《Polymer International》1985,17(4):327-329
The oligosaccharide component compositions of a series of non-reducing oligosaccharides extracted from the roots of Arnica montana L. has been determined by gel permeation chromatography (g.p.c.). The range of oligosaccharides present was found to extend beyond the octasaccharide previously reported. with 16% to 19% of the oligosaccharides having a degree of polymerisation of between 11 and 19 and almost 3% having a degree of polymerisation greater than 20. The chromatographic behaviour of this series of oligosaccharides is compared with that observed for series of D-gluco-oligosaccharides. 相似文献
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James Charles Tomas Pfister Mark Everingham Andrew Zisserman 《International Journal of Computer Vision》2014,110(1):70-90
We present a fully automatic arm and hand tracker that detects joint positions over continuous sign language video sequences of more than an hour in length. To achieve this, we make contributions in four areas: (i) we show that the overlaid signer can be separated from the background TV broadcast using co-segmentation over all frames with a layered model; (ii) we show that joint positions (shoulders, elbows, wrists) can be predicted per-frame using a random forest regressor given only this segmentation and a colour model; (iii) we show that the random forest can be trained from an existing semi-automatic, but computationally expensive, tracker; and, (iv) introduce an evaluator to assess whether the predicted joint positions are correct for each frame. The method is applied to 20 signing footage videos with changing background, challenging imaging conditions, and for different signers. Our framework outperforms the state-of-the-art long term tracker by Buehler et al. (International Journal of Computer Vision 95:180–197, 2011), does not require the manual annotation of that work, and, after automatic initialisation, performs tracking in real-time. We also achieve superior joint localisation results to those obtained using the pose estimation method of Yang and Ramanan (Proceedings of the IEEE conference on computer vision and pattern recognition, 2011). 相似文献
17.
CLATHRATE HYDRATE FORMATION ENHANCES NEAR-CRITICAL AND SUPERCRITICAL SOLVENT EXTRACTION EQUILIBRIA 总被引:3,自引:0,他引:3
Richard C. Willson Eric Bulot Charles L. Cooney 《Chemical Engineering Communications》1990,95(1):47-55
Pre-concentration of dilute aqueous solutions by hydrate formation can improve the effective distribution coefficient and selectivity of solvent extraction. Many solvents can serve simultaneously to promote solution concentration by hydrate formation and also to extract non-polar solutes from the resulting concentrated solution. This concept is illustrated for systems with supercritical ethylene and with near-critical liquid carbon dioxide, and its application to conventional solvents is discussed. 相似文献
18.
Sykes EC Han P Kandel SA Kelly KF McCarty GS Weiss PS 《Accounts of chemical research》2003,36(12):945-953
Adsorbate interactions and reactions on metal surfaces have been investigated using scanning tunneling microscopy. The manners in which adsorbates perturb the surface electronic structure in their vicinity are discussed. The effects these perturbations have on other molecules are shown to be important in overlayer growth. Interactions of molecules with surface steps are addressed, and each molecule's electron affinity is shown to dictate its adsorption sites at step edges. Standing waves emanating from steps are demonstrated to effect transient molecular adsorption up to 40 A away from the step edge. Halobenzene derivatives are used to demonstrate how the surface is important in aligning reactive intermediates. 相似文献
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Dorsa Parviz Fahmida Irin Smit A. Shah Sriya Das Charles B. Sweeney Micah J. Green 《Advanced materials (Deerfield Beach, Fla.)》2016,28(40):8796-8818
Recent developments in the exfoliation, dispersion, and processing of pristine graphene (i.e., non‐oxidized graphene) are described. General metrics are outlined that can be used to assess the quality and processability of various “graphene” products, as well as metrics that determine the potential for industrial scale‐up. The pristine graphene production process is categorized from a chemical engineering point of view with three key steps: i) pretreatment, ii) exfoliation, and iii) separation. How pristine graphene colloidal stability is distinct from the exfoliation step and is dependent upon graphene interactions with solvents and dispersants are extensively reviewed. Finally, the challenges and opportunities of using pristine graphene as nanofillers in polymer composites, as well as as building blocks for macrostructure assemblies are summarized in the context of large‐scale production. 相似文献