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991.
992.
993.
Potential of fibrous adsorbents for the binding and characterization of Porphyridium purpureum bioactive polysaccharides 下载免费PDF全文
994.
Dr. Tobias J. Zimmermann Marco Bürger Prof. Dr. Etsu Tashiro Dr. Yasumitsu Kondoh Nancy E. Martinez Dr. Kristina Görmer Sigrid Rosin‐Steiner Dr. Takeshi Shimizu Dr. Shoichiro Ozaki Dr. Katsuhiko Mikoshiba Dr. Nobumoto Watanabe Prof. Dr. Dennis Hall Dr. Ingrid R. Vetter Prof. Dr. Hiroyuki Osada Dr. Christian Hedberg Prof. Dr. Herbert Waldmann 《Chembiochem : a European journal of chemical biology》2013,14(1):115-122
Ras proteins are of importance in cell proliferation, and hence their mutated forms play causative roles in many kinds of cancer in different tissues. Inhibition of the Ras‐depalmitoylating enzyme acyl protein thioesterases APT1 and ‐2 is a new approach to modulating the Ras cycle. Here we present boronic and borinic acid derivatives as a new class of potent and nontoxic APT inhibitors. These compounds were detected by extensive library screening using chemical arrays and turned out to inhibit human APT1 and ‐2 in a competitive mode. Furthermore, one of the molecules was demonstrated to inhibit Erk1/2 phosphorylation significantly. 相似文献
995.
In this work we present the latest design of the Vienna type Differential Mobility Analyzer (DMA). The so-called UDMA is specially designed for high-resolution mobility measurements for the particle size range between 1 and 5 nm and has been optimized to be combined with a mass spectrometer to provide a well-defined mobility fraction of molecular clusters. As the UDMA is designed for this narrow size range it features high-resolution mobility measurements already at flow rates of approximately 700 L/min, marked as medium flow conditions. This readily allows operating the UDMA in a recirculating sheath air flow system with gas cleaning filters, as the control over the purity of the sheath air is crucial for operating the UDMA inline with a mass spectrometer or other carrier gas sensible devices. The performance of the newly developed UDMA was tested by the analysis of well-defined molecular clusters produced by an electrospray source and compared with one of the state-of-the-art high resolution DMAs also known as “Attoui DMA.” For the UDMA, a relative FWHH of the transfer function of 2.5% in mobility-size was found for the monomer clusters of Tetraheptylammoniumbromide (THAB) at 1.44 nm mobility equivalent diameter. 相似文献
996.
F. Streichsbier H. Rainbauer J. Washütt G. Kroyer I. Steiner N. Winker 《European Journal of Lipid Science and Technology》1982,84(8):304-308
Microbiological Investigations with Ozonized Olive Oil The general bactericide effect of ozonized olive oil was proved for various strains of bacteria. The most significant destruction effect was found for staphylococcus aureus; cultures of this strain, 24 hours old, showed a relative destruction effect of 99.9% after application of 1% inhibitor concentration with 90 min. duration of action. It was found that the staphylococcus aureus cells during the exponential growth of the period have a decadic rate of dying-back of about one per hour. The destruction effects, caused by freshly ozonized olive oil, differed only to a low extent from those of the ozonized olive oil stored for eight years. 相似文献
997.
Ivana?PoustkováEmail author Jaroslav?Dobiá? Ingrid?Steiner Jan?Poustka Michal?Vold?ich 《European Food Research and Technology》2004,219(5):534-539
Varnishes used for the inner coatings of food cans are often based on epoxy resins or vinylic organosols. The epoxy resins can be produced from bisphenol A (BPA) and bisphenol F (BPF), and these also contain bisphenol A diglycidyl ether (BADGE) or bisphenol F diglycidyl ether (BFDGE) as stabilising components. These compounds may break down during storage and also by the influence of food simulants. The stability of BADGE and BFDGE were studied using reverse-phase gradient high-performance liquid chromatography (RP-HPLC) with ultraviolet detection (UV). Three experimental conditions for spiked simulants were compared: (1) the storage at 25 °C (C1), (2) the storage at 40 °C (C2) and (3) the storage at 25 °C after 15 min heating at 120 °C (C3). Distilled water, 3% acetic acid and 10% ethanol were used as food simulants. It was observed that BADGE is more stabile than BFDGE. The loss of BADGE and BFDGE were minimal in 10% ethanol (39 and 46% at 25 °C, 60 and 69% at 40 °C, respectively) and highest in 3% acetic acid (60 and 63% at 25 °C, 76 and 82% at 40 °C, respectively). At experiment (C3), the hardest conditions, significant degradation was not shown in comparison with conditions (C1) and (C2), contrariwise BADGE and BFDGE in 10% ethanol were minimal degradated at conditions (C3) from all these experiments (loss of 5 and 8%, respectively). 相似文献
998.
This work considers flooding and dispersed phase holdup, with and without mass transfer, in a 7.6?cm diameter reciprocating plate extraction column using the liquid system toluene-acetone-water. The present flooding data in respect to the absence of mass transfer were well correlated by the hydrodynamic model based on the dispersion of drops by turbulent energy dissipation. During mass transfer the flooding characteristics were found to be dependent on the direction of mass transfer. Dispersed phase holdup data were obtained by two different measuring techniques. Local holdup was found to vary with column height, while the overall holdup depended on agitation speed, phase throughputs and mass transfer direction. The holdup data thus obtained are compared with data published for the case without mass transfer, and new correlations are presented. 相似文献
999.
1000.
Granular Matter - Binary mixtures of dry grains avalanching down a slope are experimentally studied to determine the interaction among coarse and fine grains and their effect on the morphology of... 相似文献