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141.
Hilt P Schieber A Yildirim C Arnold G Klaiber I Conrad J Beifuss U Carle R 《Journal of agricultural and food chemistry》2003,51(10):2896-2899
The phenolic profile of strawberry fruits (Fragaria x ananassa Duch., Rosaceae) was investigated by high-performance liquid chromatography with photodiode array detection. A peak displaying retention time and UV spectral data identical to those of phloridzin (phloretin 2'-O-beta-d-glucoside), a dihydrochalcone glucoside so far considered characteristic of apples, was monitored. For further characterization, crude extracts of strawberries were purified on polyamide, and the target compound was isolated by preparative and analytical HPLC. Structure elucidation was performed on the basis of APCI- and ESI-MS in the negative ion mode as well as by 1D and 2D NMR spectroscopy using authentic phloridzin for comparison. The d-configuration of the sugar moiety was established by HPLC analysis of the corresponding acyclic 1-deoxy-1-(N-acetyl-alpha-methylbenzylamino)alditol acetate. Apart from its chemotaxonomic relevance, this first report on the occurrence of phloridzin in strawberries is of particular interest for the authenticity control of strawberry products such as juices, jams, and fruit preparations since phloridzin has so far been used for the detection of fraudulent admixtures. 相似文献
142.
Andreas Krein Merce Salvia-Castellvi Jean Francois Iffly Laurent Pfister Lucien Hoffmann 《Water, air, and soil pollution》2007,182(1-4):357-368
Runoff events were analysed in separated sewer systems in the town of Luxembourg. The relationships between Event Mean Concentrations of different pollutants and runoff patterns were evaluated. In addition, the inter-storm and intra-storm variability of the material transport were determined. Primarily, the variations in pollutant concentrations and loads are determined by the antecedent weather conditions. The presence of illicit sanitary inputs in one of the sewers produced a significant first flush effect as well as higher Event Mean Concentrations for pollutants. Furthermore, near the town of Trier 40 storms were analyzed in a small natural basin mainly influenced by runoff from a separated sewer system. Natural and artificial storm events were investigated in order to estimate the relationship between the pollutant sources in the channel and from the separated sewer system. Just like in the canalization of Luxembourg City the pollutant dynamics during natural storms are strongly influenced by pre-event hydrological conditions. The artificial storms behave differently. Despite little pre-rain, the maximum concentrations of toxic substances are comparatively low. A resuspension of sediment only occurs in the natural channel system, without the introduction of fines from the sewer system. 相似文献
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The percentual composition of unesterified fatty acids in M. longissimus dorsi was determined by means of gas chromatography, and its correlations with the given genotype and pork condition were studied. Polyene fatty acids recorded from the Piétrain race deviated (C-18:2, C-18:3, C-20:4) from values recorded from large white and improved land race pigs. Animals of PSE nature were like Piétrain probands, in that their monoene acids were higher and diene acids lower by percentage than the comparable values in animals of normal pork condition. 相似文献
145.
Ultrasonography must be used in combination with physical examination for the appropriate diagnosis of acute tendon injuries. Therapy should be designed to return the tendon to its normal function and appearance. Local and systemic anti-inflammatory agents, cold hydrotherapy and massage minimize excessive scar formation and progressively increasing tensile forces directs scar tissue to replace the tendon function. 相似文献
146.
Droplets were released from an ‘instantaneous line source’ perpendicular to the wind at heights of 4 and 7 m above the ground. Droplets were collected by rotating samplers at three heights; sets of samplers were positioned in a line parallel to the wind, downwind of the line source. Trials were carried out in moderately unstable conditions during the day, and under stable conditions shortly after dark, both over short rough stubble and over mature cotton. A substantial proportion of the small droplets were found to travel as far as 500 m over cotton; over grass, few of even the smallest droplets were collected 250 and 500 m downwind of the line source. Collection at the distant samplers was on average slightly, but not significantly, more when the spray was released at the greater height. 相似文献
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The California net energy system has gained wide acceptance as a method for predicting rates of gain in growing and finishing beef animals. Researchers at the University of Kentucky, in co-operation with agricultural scientists in two regional research projects, NC-114 and S-156, have developed an interactive model that enhances the usefulness of the net energy system by including skeletal size, feed quality, temperature and relative humidity to determine feed intake and utilisation. Basically, the intake based on feed availability, nutrient composition, potential skeletal size and heat loss potential. After the feed is consumed, it is utilised according to the productive status of the animal, i.e. growth, lactation, foetal development, etc., using a modified form of the net energy system to predict weight change.The model allows a researcher to easily modify environment, feed, breed characteristics and productive status so as to evaluate their influence on the performance of the animal. 相似文献
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