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71.
Two decades of p‐phenylenediamine and toluene‐2,5‐diamine patch testing – focus on co‐sensitizations in the European baseline series and cross‐reactions with chemically related substances 下载免费PDF全文
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Wild‐type isolates of Porphyromonas gingivalis derived from periodontitis patients display major variability in platelet activation 下载免费PDF全文
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Ulyana M. Zavorotnaya Igor I. Ponomarev Yulia A. Volkova Alexander D. Modestov Vladimir N. Andreev Alexei F. Privalov Michael Vogel Vitaly V. Sinitsyn 《Materials》2020,13(22)
The sulfonated polynaphthoyleneimide polymer (co-PNIS70/30) was prepared by copolymerization of 4,4′-diaminodiphenyl ether-2,2′-disulfonic acid (ODAS) and 4,4’-methylenebisanthranilic acid (MDAC) with ODAS/MDAC molar ratio 0.7/0.3. High molecular weight co-PNIS70/30 polymers were synthesized either in phenol or in DMSO by catalytic polyheterocyclization in the presence of benzoic acid and triethylamine. The titration reveals the ion-exchange capacity of the polymer equal to 2.13 meq/g. The membrane films were prepared by casting polymer solution. Conductivities of the polymer films were determined using both in- and through-plane geometries and reached ~96 and ~60 mS/cm, respectively. The anisotropy of the conductivity is ascribed to high hydration of the surface layer compared to the bulk. SFG NMR diffusometry shows that, in the temperature range from 213 to 353 K, the 1H self-diffusion coefficient of the co-PNIS70/30 membrane is about one third of the diffusion coefficient of Nafion® at the same humidity. However, temperature dependences of proton conductivities of Nafion® and of co-PNIS70/30 membranes are nearly identical. Membrane–electrode assemblies (MEAs) based on co-PNIS70/30 were fabricated by different procedures. The optimal MEAs with co-PNIS70/30 membranes are characterized by maximum output power of ~370 mW/cm2 at 80 °C. It allows considering sulfonated co-PNIS70/30 polynaphthoyleneimides membrane attractive for practical applications. 相似文献
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In Germany vaccination with conjugated meningococcus C (MenC) vaccine is part of the national immunization program. Polysaccharide and conjugate vaccines against meningococci A, C, W135 and Y are available and used according to the recommendations of the standing committee (STIKO). Since 2013 a new recombinant 4-component meningococcus B vaccine (4CMenB) has been approved. The strain coverage of this vaccine in Europe is approximately 80?%. Immunogenicity and safety data for various vaccine schedules were generated in several studies as well as for co-administration with routine vaccines which leads to higher fever rates. No recommendations from the STIKO are currently available for 4CMenB vaccines. 相似文献
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Susan Brown Nicholas Dragann Wolfgang H. Vogel PhD 《Archives of environmental & occupational health》2013,68(3):370-372
Under the conditions employed lead acetate in toxic quantities had no significant effects on learning or memory in rats. 相似文献
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