No abstract

Many aspects of the supposed hyperthermal Toarcian Oceanic Anoxic Event (T-OAE, Early Jurassic, c. 182 Ma) are well understood but a lack of robust palaeotemperature data severely limits reconstruction of the processes that drove the t-oAe and associated environmental and biotic changes. new oxygen isotope data from calcite shells of the benthic fauna suggest that bottom water temperatures in the western Tethys were elevated by c. 3.5 °C through the entire T-OAE. Modelling supports the idea that widespread marine anoxia was induced by a greenhouse-driven weathering pulse, and is compatible with the OAE duration being extended by limitation of the global silicate weathering flux. In the western Tethys Ocean, the later part of the T-OAE is characterized by abundant occurrences of the brachiopod Soaresirhynchia, which exhibits characteristics of slow-growing, deep sea brachiopods. The unlikely success of Soaresirhynchia in a hyperthermal event is attributed here to low metabolic rate, which put it at an advantage over other species from shallow epicontinental environments with higher metabolic demand.

In this study, we present an ionotropic gelation route for obtaining porous alumina/silica microbeads (MBs) with tailorable morphology, specific surface area (SBET), and pore size, which can directly be sintered into porous, monolithic adsorbents (MAds). After sintering, SBETs from 20 m2/g up to 70 m2/g with open porosities up to 90% could be achieved depending on the silica nanoparticle addition. Due to the significantly increased SBET, a more than 100‐fold faster uptake of model dye molecules was obtained. Pore sizes ranged between 13 and 184 nm with adjustable mono‐ and bimodal size distributions. Depending on silica content and sintering temperature, the MBs were also found to be chemically stable in technologically relevant solvents such as water, acetone, acetonitrile, hydrochloric acid, and methanol for at least 1 week except for sodium hydroxide. By adjusting the processing parameters, spherical, fibrous or irregular microbead morphologies could be obtained. The same route was also successfully applied for obtaining calcium phosphate, titania, and zirconia microbeads. The presented straight‐forward ionotropic gelation route is basically applicable to any other ceramic material and therefore extremely versatile. The obtained MBs and MAds can be further adapted to any type of environmental or biotechnological purification process by additional functionalization steps.

Protein adsorption onto hydrophobic chromatographic supports has been investigated using a colloid theory surface energetics approach. The surface properties of commercially available chromatographic beads, Toyopearl Phenyl 650-C, and Toyopearl Butyl 650-C, have been experimentally determined by contact angle and zeta potential measurements. The adsorption characteristics of these beads, which bear the same backbone matrix but harbor different ligands, have been studied toward selected model proteins, in the hydrated as well as dehydrated state. There were two prominent groups of proteins observed with respect to the chromatographic supports presented in this work: loosely retained proteins, which were expected to have lower average interaction energies, and the strongly retained proteins, which were expected to have higher average interaction energies. Results were also compared and contrasted with calculations derived from adsorbent surface energies determined by inverse liquid chromatography. These results showed a good qualitative agreement, and the interaction energy minima obtained from these extended Derjaguin, Landau, Verwey and Overbeek calculations were shown to correlate well with the experimentally determined adsorption behavior of each protein.

In this study, we present porous ceramics combining the antibacterial effect of copper with an integrated copper removal adsorbent. After preparing and characterizing the antibacterial copper-doped microbeads and monoliths (CuBs and CuMs), their antibacterial efficiency is probed against different nonpathogenic and pathogenic bacteria (Bacillus subtilis, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa). An antibacterial efficiency of 100% is reached within 15 min to 3 h for all tested strains under static conditions. Dynamic tests with B. subtilis and E. coli showed high antibacterial efficiency up to 99.93% even at continuous flux. To avoid any adverse effects on the environment, continuous removal of released copper-ions is accomplished with porous, high surface area monolithic adsorbents (MAds). MAds are prepared similarly to the CuMs but without adding copper during the manufacturing process. MAds reduce the amount of copper released from the CuMs ≥ 99% during the first 15 min, ≥90% up to 2 h, and after 22 h of continuous filtration up to 56% of the released copper is removed.