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61.
Chemical basis of anti-listerial effects of rosemary herb during stomaching with fresh-cut vegetables 总被引:2,自引:0,他引:2
Fresh rosemary herb has demonstrated much stronger anti-listerial effects when stomached with contaminated fresh-cut vegetables than those obtained by application of rosemary essential oils. Various types of rosemary extracts (hydrodistillates, CO2 extracts, hexane/acetone extracts) were analysed by GC–MS and tested for anti-listerial effects in vitro. Principal component analysis showed that verbenone levels were most correlated with anti-listerial effects, followed by levels of camphor. Stomaching rosemary herb greatly increased headspace levels of verbenone and camphor (by up to 20 times) compared to intact or chopped fresh rosemary. It is speculated that by crushing the herb under water, stomaching released enhanced levels of these components as lipophilic nanosomes which rapidly migrated to lipophilic surfaces, including the membranes of Listeria cells. 相似文献
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Johann Borenstein 《国际生产研究杂志》2013,51(9):1993-2010
This paper introduces a new automated guided vehicle (AGV) for guidewire-free industrial applications where rapid reconfiguration is required. The AGV, called OmniMate, has full omnidirectional motion capabilities, can correct odometry errors without external references, and offers a large 183 x 91 cm (72 x 36 in) loading deck. A patented, so-called compliant linkage avoids the excessive wheel slippage often found in other omnidirectional platforms. The paper describes the kinematic design and the control system of the platform and explains its unique odometry error correction method, called internal position error correction (IPEC). IPEC renders the OmniMate's odometry almost completely insensitive to even severe irregularities of the floor, such as bumps, cracks, or traversable objects. Dead-reckoning is enhanced further by the addition of a fibre-optics gyroscope. Because of its extraordinary dead-reckoning capabilities the OmniMate can travel over extended distances while following a pre-programmed path fully automatically. The paper describes an implemented 'leadthrough' teaching system, in which an operator guides the OmniMate along a desired path, while the OmniMate records the path to memory. Later, in path execution mode, the OmniMate reproduces the path accurately, observing commanded velocities. With this system it is possible and feasible to program or modify a complete path within minutes. 相似文献
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Johann Bizer 《Datenschutz und Datensicherheit - DuD》2008,32(7):435-435
Ohne Zusammenfassung 相似文献
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The Almbach, a headwater stream in the Upper Austrian foothills of the Alps bordered by mountain pastures was studied to gain insight into the benthic macroinvertebrate community and its habitat. Two springs, one of them fenced in to prevent livestock access, and two more sites of the headwater section were investigated. A discriminant analysis (DA) based on hydrochemistry and phytobenthos revealed three functions with 86% of all samples correctly classified to the four sites. The first function clearly separated the two springs with phosphorus and oxygen as the most important discriminating factors. Spring sites and headwater sites were split up by the second function mainly due to nitrate concentration, but no differences could be detected for the two stream sites. With the exception of the fenced spring, indicator taxa could be assigned to all sites by means of an Indicator Species Analysis (ISA). Polyvalent taxa groups such as Gastropoda and Ostracoda were indicators for the unfenced spring site. This is in accordance to observed low abundances of sensitive plecopteran taxa and suggests a negative impact of livestock trampling on the invertebrate community. Redundancy Analysis explained 99% of the macroinvertebrate‐environment relation. The first axis separated springs from stream sites and was correlated with nitrate, pH, water temperature and phytobenthos eveness. Phosphorus was responsible for splitting the unfenced spring and the downstream station from the fenced spring and the upstream location along the second axis. Ephemeropteran taxa like Habrophlebia sp. were related to elevated pH, increased water temperature and low nitrate concentrations. In accordance to the ISA, nitrate played an important role for tolerant Gastropoda and Ostracoda at the unfenced spring. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Periodic mesoporous silica was modified with metal organic reagents via direct surface substitution reactions, thus introducing functional groups into the channels of the structure. Using materials functionalised with basic aromatic molecules as catalysts, the efficient Michael addition of diethyl malonate to trans-β-nitrostyrene was achieved. The catalysts anchored to the silica surface show high activity in the catalytic process even at low concentrations and low temperatures. The catalysts also prove to be stable during many recycling procedures. In combination with the remarkably reduced cost for the synthesis of these solid bases, the new hybrid systems are promising candidates for a new generation of catalysts. 相似文献