Pelagic molybdenum concentration anomalies and the impact of sediment resuspension on the molybdenum budget in two tidal systems of the North Sea

The seasonal dynamics of molybdenum (Mo) were studied in the water column of two tidal basins of the German Wadden Sea (Sylt-Rømø and Spiekeroog) between 2007 and 2011. In contrast to its conservative behaviour in the open ocean, both, losses of more than 50% of the usual concentration level of Mo in seawater and enrichments up to 20% were observed repeatedly in the water column of the study areas. During early summer, Mo removal by adsorption on algae-derived organic matter (e.g. after Phaeocystis blooms) is postulated to be a possible mechanism. Mo bound to organic aggregates is likely transferred to the surface sediment where microbial decomposition enriches Mo in the pore water. First δ98/95Mo data of the study area disclose residual Mo in the open water column being isotopically heavier than MOMo (Mean Ocean Molybdenum) during a negative Mo concentration anomaly, whereas suspended particulate matter shows distinctly lighter values. Based on field observations a Mo isotope enrichment factor of ε = −0.3‰ has been determined which was used to argue against sorption on metal oxide surfaces. It is suggested here that isotope fractionation is caused by biological activity and association to organic matter. Pelagic Mo concentration anomalies exceeding the theoretical salinity-based concentration level, on the other hand, cannot be explained by replenishment via North Sea waters alone and require a supply of excess Mo. Laboratory experiments with natural anoxic tidal flat sediments and modelled sediment displacement during storm events suggest fast and effective Mo release during the resuspension of anoxic sediments in oxic seawater as an important process for a recycling of sedimentary sulphide bound Mo into the water column.

Composition Space Analysis in the Development of Copper Molybdate Hybrids Decorated by a Bifunctional Pyrazolyl/1,2,4-Triazole Ligand

A bitopic ligand, 4-(3,5-dimethylpyrazol-4-yl)-1,2,4-triazole (Hpz-tr) (1), containing two different heterocyclic moieties was employed for the design of copper(II)–molybdate solids under hydrothermal conditions. In the multicomponent CuII/Hpz-tr/MoVI system, a diverse set of coordination hybrids, [Cu(Hpz-tr)2SO4]·3H2O (2), [Cu(Hpz-tr)Mo3O10] (3), [Cu4(OH)4(Hpz-tr)4Mo8O26]·6H2O (4), [Cu(Hpz-tr)2Mo4O13] (5), and [Mo2O6(Hpz-tr)]·H2O (6), was prepared and characterized. A systematic investigation of these systems in the form of a ternary crystallization diagram approach was utilized to show the influence of the molar ratios of starting reagents, the metal (CuII and MoVI) sources, the temperature, etc., on the reaction products outcome. Complexes 2–4 dominate throughout a wide crystallization range of the composition triangle, while the other two compounds 5 and 6 crystallize as minor phases in a narrow concentration range. In the crystal structures of 2–6, the organic ligand behaves as a short [N–N]-triazole linker between metal centers Cu···Cu in 2–4, Cu···Mo in 5, and Mo···Mo in 6, while the pyrazolyl function remains uncoordinated. This is the reason for the exceptional formation of low-dimensional coordination motifs: 1D for 2, 4, and 6 and 2D for 3 and 5. In all cases, the pyrazolyl group is involved in H bonding (H-donor/H-acceptor) and is responsible for π–π stacking, thus connecting the chain and layer structures in more complicated H-bonding architectures. These compounds possess moderate thermal stability up to 250–300 °C. The magnetic measurements were performed for 2–4, revealing in all three cases antiferromagnetic exchange interactions between neighboring CuII centers and long-range order with a net moment below Tc of 13 K for compound 4.

Collecting the Painted Netherlands: The Art Collection of Ernest of Austria in Brussels

The (art) collection of Archduke Ernest of Austria (1553-1595) is widely unknown when it comes to early-modern Habsburg collections. Ernest, younger brother of Emperor Rudolf II (b. 1552) and educated at the Madrid court, was appointed Governor-General of the Netherlands by King Philip II of Spain, his uncle, in summer 1593. Ernest relocated his court from Vienna to Brussels in early 1594 and was welcomed there with lavish festivities: the traditional Blijde Inkomst, Joyous Entry, of the new sovereign. Unfortunately, the archduke died in February 1595 after residing in Brussels for a mere thirteen months. This investigation aims to shed new light on the archduke and his short-lived collecting ambitions in the Low Countries, taking into account that he had the mercantile and artistic metropolis Antwerp in his immediate reach. I argue, that his collecting ambitions can be traced back to one specific occasion: Ernest’s Joyous Entry into Antwerp in June 1594. There the archduke received a series of six paintings of Pieter Bruegel the Elder (1525/30-1569) known as The Months (painted in 1565), hanging today in separate locations in Vienna, New York and Prague. These works of art triggered Ernest’s collecting ambitions and prompted him to focus mainly on works of art and artefacts manufactured at or traded within the Netherlands during the last eight months of his lifetime. Additionally, it will be shown that the archduke was inspired by the paintings’ motifs and therefore concentrated on acquiring works of art depicting nature and landscape scenes from the 1560s and 1590s. On the basis of the archduke’s recently published account book (Kassabuch) and of the partially published inventory of his belongings, it becomes clear that Ernest of Austria must be seen in line with the better-known Habsburg collectors and that his specific collection of “the painted Netherlands” can be linked directly to his self-fashioning as a rightful sovereign of the Low Countries.

The Forgotten Archduke: The Funeral Monument for Ernest of Austria in Brussels

Archduke Ernest of Austria (1553–1595), second son of Emperor Maximilian II and younger brother of Emperor Rudolf II, was in his youth a possible candidate for the thrones of the Empire or the Spanish Kingdom. Instead, he became Governor-General of the Netherlands in 1593 and relocated to Brussels in 1594 where he was welcomed with lavish festivities as the bearer of hope and prosperity. Unfortunately, Ernest died only thirteen months later without having achieved any political success. His brother and successor Albert of Austria commissioned the funeral monument for Ernest in 1600 after it was settled that he would be buried in Brussels and not Vienna. Focusing on this monument, which draws stylistically from various dynasty-related models, it will be shown that Albert intended to use this monument – and thus his brother’s memoria – to make the Brussels Cathedral the primary location of Habsburg dynastic memory in the Low Countries.