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Dr. Klas Bratteby Dr. Vladimir Shalgunov Prof. Matthias Manfred Herth 《ChemMedChem》2021,16(17):2612-2622
Aliphatic fluorine-18 radiolabeling is the most commonly used method to synthesize tracers for PET-imaging. With an increasing demand for 18F-radiotracers for clinical applications, new labeling strategies aiming to increase radiochemical yields of established tracers or, more importantly, to enable 18F-labeling of new scaffolds have been developed. In recent years, increased attention has been focused on the direct aliphatic 18F-fluorination of base-sensitive substrates in this respect. This minireview gives a concise overview of the recent advances within this field and aims to highlight the advantages and limitations of these methods. 相似文献
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Front Cover: Photoactivatable Mussel‐Based Underwater Adhesive Proteins by an Expanded Genetic Code (ChemBioChem 18/2017)
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Dr. Matthias Hauf Dr. Florian Richter Tobias Schneider Thomas Faidt Dr. Berta M. Martins Dr. Tobias Baumann Dr. Patrick Durkin Prof. Dr. Holger Dobbek Prof. Dr. Karin Jacobs Prof. Dr. Andreas Möglich Prof. Dr. Nediljko Budisa 《Chembiochem : a European journal of chemical biology》2017,18(18):1771-1771
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László Papp Matthias Sipiczki Imre J. Holb Ida Miklós 《Yeast (Chichester, England)》2014,31(12):475-482
The non‐pathogenic dimorphic fission yeast, Schizosaccharomyces japonicus, could be a suitable model organism for investigation of the genetic background of mycelial growth, as it has a haploid chromosome set and its genome is sequenced. Since earlier results have suggested that its morphological transition required solid substrates, but molecular biological experiments would require hyphae production in a liquid medium, we wanted to find circumstances which would enable hyphae production in liquid media. Several external conditions were investigated, but the strongest inducer was fetal bovine serum (FBS). Its positive effect could be hampered by heat and was dependent on pH, temperature and concentration of the serum. Other protein‐containing compounds, such as peptone and bovine serum albumin or amino acids, proved to be ineffective or weak. Generally, the uninduced and induced mycelial growth of Sz. japonicus could be improved by lower external pH and higher temperature. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Matthias Schulz Ute Pippardt Lutz Kiesel Katrin Ritter Ralf Kriegel 《American Institute of Chemical Engineers》2012,58(10):3195-3202
Ba0.5Sr0.5Co0.8Fe0.2O3‐δ tubes, capillaries, capillary modules, and asymmetric membranes were prepared and tested for oxygen permeation in a dead‐end vacuum operation mode at temperatures up to 850°C. The capillary module was built up by reactive air brazing using seven capillaries and a supply tube. Two machined discs were used as an end cap and as a connector plate. The oxygen permeation behaves according to Wagner at small driving forces, but significant negative deviations were observed for asymmetric membranes and single capillaries at higher ones. This is caused by pressure drops at the vacuum side for single capillaries. The highest oxygen flux was revealed for the capillary module with 175.5 mL(STP)/min at a low‐vacuum pressure of 0.042 bar at 850°C, but the asymmetric membrane showing a little bit higher flux at moderate vacuum pressures above 0.07 bar. © 2012 American Institute of Chemical Engineers AIChE J, 58: 3195–3202, 2012 相似文献
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Rolling Bearings For The Use In Vacuum The use of rolling bearings in vacuum is limited due to technical reasons regarding the standard lubricants. Nevertheless there are options to use those machine elements anyways. Therefore an alternative lubrication, e.g. Molybdenum Disulfide, will be applied successfully. as a result rolling bearings can be used in surroundings with high temperatures as well as in vacuum. The following describes how the assume the lifetime of rolling bearings and shows how to optimize the systems with respect to its lifetime and therewith to the costs of the element by using it within such extreme surroundings. The shown options then will be proved by experimental tests. 相似文献
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This article presents a thorough statistical analysis of the capacity of orthogonal space-time block coded (OSTBC) multiple-input multiple-output (MIMO) Nakagami- lognormal (NLN) channels. The NLN channel model allows to study the joint effects of fast fading and shadowing on the statistical properties of the channel capacity. We have derived exact analytical expressions for the probability density function (PDF), cumulative distribution function (CDF), level-crossing rate (LCR), and average duration of fades (ADF) of the capacity of MIMO NLN channels. It is observed that an increase in the MIMO dimension or a decrease in the severity of fading results in an increase in the mean channel capacity, while the variance of the channel capacity decreases. On the other hand, an increase in the shadowing standard deviation increases the spread of the channel capacity, however the shadowing effect has no influence on the mean channel capacity. We have also presented approximation results for the statistical properties of the channel capacity, obtained using the Gauss-Hermite integration method. It is observed that approximation results not only reduce the complexity, but also have a very good fitting with the exact results. The presented results are very useful and general because they provide the flexibility to study the impact of shadowing on the channel capacity under different fading conditions. Moreover, the effects of severity of fading on the channel capacity can also be studied. The correctness of theoretical results is confirmed by simulations. 相似文献