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41.
Summary. Benzoic acid is a known stimulant of olfactory receptor cells in trichoid sensilla on the antennae of adult females of Bombyx mori. Exposure of freshly excised antennae, from B. mori females and males, to vapours of [14C]-benzoic acid revealed that the adsorbed acid is rapidly metabolized (15% conversion in 10 s), suggesting the presence of a highly active enzymatic system. The major product could be identified as N-benzoylserine by use of [2H5]-benzoic acid, and mass spectrometry linked to a gas chromatograph (GC-MS) or a liquid chromatograph (LC-MS), for analysis of the metabolites. The conjugation of benzoic acid with an amino acid apparently represents a novel mode for the rapid deactivation of odorant molecules. Received 26 March 2001.  相似文献   
42.
Alkaline tailings from a salt work and a soda plant have been pumped into the southernmost part of Traunsee at Ebensee for many decades. A survey in 1981 showed an accumulation of more than 3 × 106 m3 alkaline mud in the Bay of Ebensee and the existence of slumping structures and turbidites in the profundal zone of the lake. A new survey of the industrial tailings has been performed in 1999. Compared to the earlier survey, the accumulation in the Bay of Ebensee has grown to >4 × 106 m3, which suggests an average yearly input of 90 000 m3. Slumping structures and turbidites document the unstable situation of the tailings near the waste inlet. The lake area occasionally affected by the turbidity currents in the profundal zone has increased to 19%. Within the central profundal area these tailings reach <1 m in thickness.  相似文献   
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For governments and for manufacturing companies, global warming, rising energy prices, and customers’ increasing ecological awareness have pushed energy efficient manufacturing to the top of the agenda. Governments and companies are both striving to identify the most effective measures to increase energy efficiency in manufacturing processes. Based on results of a recent EU-funded roadmapping project, this paper highlights the needs of industrial companies for integrating energy efficiency performance in production management. First, it analyses concepts and tools for measurement, control and improvement of energy efficiency in production management proposed in literature. Second, the paper outlines that ICT tools and standardization are important enablers for energy efficient manufacturing. Third, industrial needs in these areas are presented based on expert interviews. The industrial needs thus identified are contrasted with concepts proposed in literature to point out the implementation gaps between practice and theory. The paper demonstrates that there exists a gap between the solutions available and the actual implementation in industrial companies. It concludes by deriving requirements for energy management in production that future collaborative research projects should address.  相似文献   
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Magnetic resonance imaging (MRI) appears to be increasingly used, in addition to standard ultrasonography for the diagnosis of abnormalities in utero. Previous studies have recently drawn attention to the technical refinement of MRI to visualize the fetal bones and muscles. Beyond commonly used T2-weighted MRI, echoplanar, thick-slab T2-weighted and dynamic sequences, and three-dimensional MRI techniques, are about to provide new imaging insights into the normal and the pathological musculoskeletal system of the fetus. This review emphasizes the potential significance of MRI in the visualization of the fetal musculoskeletal system. © 2012 John Wiley & Sons, Ltd.  相似文献   
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The 17th BlmSchV fixed the emission limit of 0.1 ng TE/mn 3 for PCDD/F’s produced as a result of waste- and special waste incinerators. This article introduces the different measures implemented to uphold this limit, and discusses their advantages and disadvantages. Methods of optimising the incineration conditions are among the primary measures. Different geometry’s for conventional oven incineration rooms were discussed, and an effective modernisation method was introduced (Temelli nozzles). The chemical and technical basis of an often discussed gasification method, as well as the characteristics of three specialised techniques (Coke Burn technique, Thermo-Select technique and Noell-DBI technique) are explained in this article. Alongside the secondary measures of hot-dust filtration and inhibition being added to the washers in an attempt to achieve PCDD/F adsorption. The most important tertiary measures, namely the SCR technique, along with a variety of coke adsorption techniques are introduced, with their advantages and disadvantages. New techniques such as DeDioxin and Medisorbon are also addressed.  相似文献   
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