Hydrogen-bonded network structures in dipyridinium, bis(2-methylpyridinium), bis3-methylpyridinium) and bis(4-methylpyridinium) dioxidobisoxydiacetato)urante (VI)

Four complexes containing the [UO(2)(oda)(2)](2−) anion (oda is oxy­diacetate) are reported, namely dipyridinium dioxidobis(oxydiacetato)uranate(VI), (C(5)H(6)N)(2)[U(C(4)H(4)O(5))(2)O(2)], (I), bis(2-methyl­pyridinium) dioxidobis(oxydiacetato)uranate(VI), (C(8)H(8)N)(2)[U(C(4)H(4)O(5))(2)O(2)], (II), bis­(3-methyl­pyridinium) di­oxido­bis(oxydiacetato)uranate(VI), (C(8)H(8)N)(2)[U(C(4)H(4)O(5))(2)O(2)], (III), and bis­(4-methyl­pyridinium) dioxidobis(oxydiacetato)uranate(VI), (C(8)H(8)N)(2)[U(C(4)H(4)O(5))(2)O(2)], (IV). The anions are achiral and are located on a mirror plane in (I) and on inversion centres in (II)–(IV). The four complexes are assembled into three-dimensional structures via N—H⋯O and C—H⋯O inter­actions. Compounds (III) and (IV) are isomorphous; the [UO(2)(oda)(2)](2−) anions form a porous matrix which is nearly identical in the two structures, and the cations are located in channels formed in this matrix. Compounds (I) and (II) are very different from (III) and (IV): (I) forms a layered structure, while (II) forms ribbons

Vendor independent control database for virtual preparation and formal verification

It is very advantageous to use virtual techniques for testing and developing new hardware and software systems within a manufacturing system. It is, however, of greatest importance that the virtual model can be trusted so that the results of the development and tests can be directly transferred to a real system without any manual last minute changes. In order to trust the result, formal verification techniques can be applied and by doing that guaranteeing a correct system behavior. Today, there is a gap between how systems are modeled in simulation softwares and formal verification softwares and it is therefore hard to perform formal verification. In order to limit the risk of introducing errors it is also important that the specifications created in the simulation softwares are not manually converted into formal languages. The present paper presents a method for sharing information between the different virtual development tools and formal verification tools. A database, storing necessary control information for verification and controller synthesis, is presented

Tuning the photochemical properties of the fulvalene-tetracarbonyl-diruthenium system

In a Molecular Solar-Thermal Energy Storage (MOST) system, solar energy is converted to chemical energy using a compound that undergoes reversible endothermic photoisomerization. The high-energy photoisomer can later be converted back to the parent compound and the excess energy is released as heat. One of the most studied MOST systems is based on fulvalene-tetracarbonyl-diruthenium, and this paper demonstrates, for the first time, the possibility to tune the photochemical properties of this system by positive steric hindrance working on the fulvalene unit

Online geometry assurance in individualized production by feedback control and model calibration of digital twins

In this paper, we consider online calibration of a Digital Twin and its use for control and optimization in the assembly process of sheet metal parts. This calibration is done based on a feedback signal received by calculating the quality of the simulated assemblies as compared to the prediction made by the Digital Twin. We develop a Kalman filter-based approach for online calibration of the Digital Twin, which in turn is used by a one-step look-ahead optimizer to define an online control scheme. This control scheme balances directly predicted quality gains against reduced uncertainty whose purpose is to enable long-term quality gains. The usage of a calibrated model in a one-step look-ahead optimizer as a controller allows to incorporate the benefits of the usage of Digital Twins for individualized control, where the control parameters of a production cell are optimized in a Digital Twin based on measured properties of the production inputs, over nominal control, where control parameters are set with respect to some reference production inputs, in an approach which is able to use measured final production quality for feedback control. The proposed approach is evaluated by computer simulations of two industrial product assembly use cases. In the first case, it demonstrates significant gains in quality of the produced assemblies, while in the second case it shows negligible to small improvements. The second case is, however, rather insensitive to miscalibration, which enables only small gains

An aqueous non-heme Fe(iv)oxo complex with a basic group in the second coordination sphere

The Fe(IV)oxo complex of a coordinatively flexible multidentate mono-carboxylato ligand is obtained by the one electron oxidation of a low spin Fe(III) precursor in water

Co-crystallizing coordination compounds

Crystallization of an equimolar mixture of 1,10-dimethylphenanthroline (DMP) and manganese(II) chloride from N,N-dimethylformamide (DMF) has been studied. Rather than a useful route to a well-defined product, it was found that identical solutions could deposit crystals of three different compounds. The most common outcome was the formation of crystals of [MnCl2(dmp)(dmf)], 1, or co-crystallization of [MnCl2(dmp)(dmf)] and [{MnCl2(dmp)}2]. The co-crystals, 2, were always found to dissolve as crystals of 1 started to grow. Crystals of a third compound, [MnCl2(dmp)2], 3, were also isolated once

A missing link between chiral four- and five-coordinate complexes

We report total spontaneous resolution and absolute asymmetric synthesis of [Pd(hfacac)(2)P(o-tol)(3)] (hfacac = hexafluoroacetylacetonate, P(o-tol)(3) = tri(o-tolyl)phosphine), a chiral complex with a coordination geometry intermediate between square-planar, square pyramidal and trigonal bipyramidal