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11.
A Complete and Highly Effective Mothproofing Agent Comprising a Pyrethroid and a Hexahydropyrimidine
Pyrethroids, considered as a general class of compounds, have been shown to provide effective protection from the larvae of the keratin-digesting insects Tineola bisselliella H., Tinea pellionella Linn., Hofmannophila pseudo-spretella Station and Attagenus piceus Oliv. The position regarding the susceptibility of the furniture carpet beetle to pyrethroids is less clear, however. It has been reported that both deltamethrin and permethrin are effective against Anthrenus flavipes Le Conte, whilst permethrin is also reported elsewhere to be effective against the same species. Results obtained in our laboratory, however, have indicated that pyrethroids may offer inadequate protection against Anthrenus vorax Waterh. [1, 2]. This latter species is identical to Anthrenus flavipes var. seminiveus Casey, a colour variety of Anthrenus flavipes Le Conte. The 1,3-disubstituted5-phenylcarbamoyl-2,4,6-trioxo- and 4,6-dioxo-2-thione-hexahydropyrimidine derivatives described in this paper exhibit a surprisingly high and selective toxicity to the Anthrenus species. Thus, a combination of an appropriate hexahydropyrimidine with a suitable pyrethroid, e.g. permethrin, provides complete control of a wide range of commonly encountered textile insect pests. The influence of substituents on the mothproofing activity is discussed. 相似文献
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Heinz E Bille 《Coloration Technology》1987,103(12):427-434
Cotton continues to be a very widely used natural fibre. However, it becomes ever more difficult to define it exactly in chemical terms, because the variety and quantity of non-cellulosic constituents in the raw cotton are continually increasing in number and becoming more difficult to specify. The textile processor can only count on 75%, or at best 80%, being genuine cellulosic material; the remainder consists mainly of impurities that can seriously interfere with subsequent processes. Modem pretreatment processes take full account of the specific quality requirements, and naturally also the relevant cost factors (energy, effluent, processing costs). By these means the bleacher can now convert raw cotton into a chemically uniform and defined cellulosic textile substrate for the subsequent processes. In this form, either alone or in blends with synthetic fibres, it is accessible for dyeing, printing and finishing processes that can be readily controlled and reproduced. 相似文献
16.
Stella Clarke Gerhard Schillhuber Michael F. Zaeh Heinz Ulbrich 《Multimedia Systems》2008,13(4):253-261
The remote nature of telepresence scenarios can be seen as a strongpoint and also as a weakness. Although it enables the remote
control of robots in dangerous or inaccessible environments, it necessarily involves some kind of communication mechanism
for the transmission of control signals. This communication mechanism necessarily involves adverse network effects such as
delay. Three mechanisms aimed at improving the effects of network delay are presented in this paper: (1) Motion prediction
to partially compensate for network delays, (2) force prediction to learn a local force model, thereby reducing dependency
on delayed force signals, and (3) haptic data compression to reduce the required bandwidth of high frequency data. The utilized
motion prediction scheme was shown to improve operator performance, but had no influence on operator immersion. The force
prediction provided haptic feedback through synchronous forces from the local model, thereby stabilizing the control loop.
The developed haptic data compression scheme reduced the number of packets sent across the network by 90%, while improving
the quality of the haptic feedback. 相似文献
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Dimitra?Giannakopoulou David?H.?Bushnell Johann?SchumannEmail author Heinz?Erzberger Karen?Heere 《Annals of Mathematics and Artificial Intelligence》2011,63(1):5-30
In order to address the rapidly increasing load of air traffic operations, innovative algorithms and software systems must
be developed for the next generation air traffic control. Extensive verification of such novel algorithms is key for their
adoption by industry. Separation assurance algorithms aim at predicting if two aircraft will get closer to each other than
a minimum safe distance; if loss of separation is predicted, they also propose a change of course for the aircraft to resolve
this potential conflict. In this paper, we report on our work towards developing an advanced testing framework for separation
assurance. Our framework supports automated test case generation and testing, and defines test oracles that capture algorithm
requirements. We discuss three different approaches to test-case generation, their application to a separation assurance prototype,
and their respective strengths and weaknesses. We also present an approach for statistical analysis of the large numbers of
test results obtained from our framework. 相似文献
19.
Yun Chen Shahbaz Khan Tariq Rana Akhtar Abbas Heinz Buettikofer 《Water Resources Management》2012,26(11):3077-3093
Australian irrigated agriculture utilises about 70?% of all water used in the country, 21?% of which is derived from groundwater. Sustainability for irrigated agriculture also depends on keeping the watertables at a safe level below the rootzone to avoid salinisation and reduction in crop yields. There is a vital need to understand groundwater and aquifer systems and their roles in the sustainability of irrigated agriculture in order to manage groundwater properly. This study builds on the previous hydrogeological and groundwater investigations of the Coleambally Irrigation Area (CIA) in New South Wales of Australia. It presents a new approach which systematically characterises regional hydrogeological environment using a three-dimensional (3-D) conceptual framework developed in ArcGIS. The 3-D hydrological conceptualisation of the CIA has integrated disparate sources of data into a coherent knowledge base for a better visualisation of hydrogeological characteristics and a comprehensive analysis of groundwater flow and aquifers. As an application example, the model was used to develop cross-sectional models of the area and to estimate regional-scale net recharge. The results have provided a basis for the numerical modelling and added values to procedures which underpin irrigation system management investment decisions through improving the understanding of hydrogeology underlying the area and creating an action-oriented dialogue among stakeholders. 相似文献
20.
Carl Heinz Brieskorn und Günter Blosczyk 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1981,172(3):201-205
Zusammenfassung Die Cuticula von Traubenschalen enthält neben Oleanolsäure noch 3-Oxo-olean-12-en28-säure, 3-Hydroxi-olean-12-en-28-aldehyd, 3,29-Dihydroxi-olean-12-en-28-säure sowie zwei bisher unbekannte Triterpensäuren. Ihre Strukturen werden durch spektroskopische Daten als 16-Hydroxi-3-oxo-olean-12-en-28-säure und 16-Hydroxi-3-oxo-oleana-1,12-dien-28-säure belegt.
New triterpenic acids from the peel of grapes
Summary The grape-cuticle contains beside oleanolic acid, 3-oxo-olean-12-en-28-oic acid, 3-hydroxy-olean-12-en-28-aldehyde, 3,29-dihydroxy-olean-12-en-28-oic acid, and two yet hitherto unknown triterpenic acids. Their structures have been elucidated by spectroscopic methods to be l6-hydroxy-3-oxo-olean-12-en-28-oic acid and 16-hydroxy-3-oxo-oleana-1,12-dien-28-oic acid.相似文献