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101.
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Michael Reinwarth Bernhard Glotzbach Michael Tomaszowski Sebastian Fabritz Dr. Olga Avrutina Prof. Dr. Harald Kolmar 《Chembiochem : a European journal of chemical biology》2013,14(1):137-146
Bioactive peptides often contain several disulfide bonds that provide the main contribution to conformational rigidity and structural, thermal, or biological stability. Among them, cystine‐knot peptides—commonly named “knottins”—make up a subclass with several thousand natural members. Hence, they are considered promising frameworks for peptide‐based pharmaceuticals. Although cystine‐knot peptides are available through chemical and recombinant synthetic routes, oxidative folding to afford the bioactive isomers still remains a crucial step. We therefore investigated the oxidative folding of ten protease‐inhibiting peptides from two knottin families, as well as that of an HIV entry inhibitor and of aprotinin, under two conventional sets of folding conditions and by a newly developed procedure. Kinetic studies identified folding conditions that resulted in correctly folded miniproteins with high rates of conversion even for highly hydrophobic and aggregation‐prone peptides in concentrated solutions. 相似文献
103.
A new catalyst WO3/ZrO2–Ce0.6Zr0.4O2 (15 wt % WO3/ZrO2:Ce0.6Zr0.4O2 = 50:50) has been developed for the selective catalytic reduction of NO with NH3. The redox component Ce0.6Zr0.4O2 was dispersed on the surface of acidic WO3/ZrO2 by the solution combustion method showing the best NO x reduction efficiency among the catalysts prepared by various modes of mixing of the components. The catalyst has been characterized by XRD, Raman spectroscopy and NH3-TPD. A NO x reduction efficiency of more than 90 % was obtained between 300 and 500 °C at α = NH3,in/NO x,in = 1. The catalyst showed stable NO x reduction efficiency after hydrothermal ageing at 700 °C. Sulfur poisoning promoted the NO x reduction efficiency at high temperatures at the expense of a reduced activity at lower temperatures, but the catalyst could be fully regenerated by heating in O2 at 650 °C. 相似文献
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This paper examines the performance of cascade‐aerated facultative ponds in a waste stabilisation pond (WSP) installation in the United Kingdom. The pond system is privately owned and treats wastewater from a conference centre with a population equivalent between 20 and 40. A snapshot analysis investigates the removal efficiency of BOD, COD, SS, FC and nutrients. Further, the oxygen supply through ‘flow form’ cascades is examined, and the DO concentrations, surface loads and retention times are discussed. The results show a very high removal of BOD, COD and SS; and nutrient removal is satisfactory. An unusual finding is that the FC removal efficiency is almost two log units better than for a common maturation pond. This is possibly attributable to the high cascade flow, where wastewater is exposed to the damaging effects of sunlight (photo‐oxidation). 相似文献
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Klaus-Peter Hinz Raimund Kaufmann Bernhard Spengler 《Aerosol science and technology》2013,47(4):233-242
ABSTRACT The instrumental setup used for simultaneous bipolar ion detection in on-line single-particle analysis by laser mass spectrometry is described. Particle size calibration has been performed using aerodynamic time-of-flight techniques. Mass spectra of several hundred ambient particles with aerodynamic diameters of 0.8 μm have been evaluated for statistical classification (Principal Components Analysis [PCA]) in order to identify main chemical components of the prominent particle classes. 相似文献
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110.
Fl��via Santos Twardowski Pinto Simone Hickmann Fl?res Carolina Elisa Schneider Marco Antonio Z��chia Ayub Plinho Francisco Hertz 《Food and Bioprocess Technology》2011,4(4):559-565
In this work, the influence of oxygen mass transfer rates on the production of cyclodextrin glycosyltransferase (CGTase) by
the alkaliphilic bacterium Bacillus circulans ATCC 21783 was investigated. Experimental design and response surface methodology were applied to optimize agitation speed
and air flow rate in batch cultivations, in order to identify their significant effects and interactions with the synthesis
of CGTase. Results were expressed as the volumetric mass transfer rates of oxygen (kla, [per hour]). The maximal CGTase productivity of 155 U mL−1 h−1 was achieved with kla of 48 h−1. CGTase production was also studied in fed-batch cultures using the optimized parameters obtained in the batch experiments.
The maximal CGTase productivity on fed-batch cultivations was 137 U mL−1 h−1 with feeding rates of starch at 0.17 g L−1 h−1. 相似文献