32 research outputs found
Synthesis, Structures, and Optical Properties of Ruthenium(II) Complexes of the Tris(1-pyrazolyl)methane Ligand
Four new complex salts [Ru^(II)Cl(Tpm)(L^A)_2][PF_6]_n [Tpm = tris(1-pyrazolyl)methane; n = 1, L^A = pyridine (py) 1 or ethyl isonicotinate (EIN) 2; n = 3, L^A = N-methyl-4,4′-bipyridinium (MeQ^+) 3 or N-phenyl-4,4′-bipyridinium (PhQ^+) 4] have been prepared and characterized. Electronic absorption spectra show intense d → π^* metal-to-ligand charge-transfer (MLCT) absorption bands, while cyclic voltammetry reveals a reversible Ru^(III/II) wave, accompanied by quasireversible or irreversible L^A-based reductions for all except 1. Single crystal X-ray structures have been obtained for 1•Me_2CO, 2, and 3•Me_2CO. For 2–4, molecular first hyperpolarizabilities β have been measured in acetonitrile solutions via the hyper-Rayleigh scattering (HRS) technique at 800 nm. Stark (electroabsorption) spectroscopic studies on the MLCT bands in frozen butyronitrile allow the indirect estimation of static first hyperpolarizabilities β_0. The various physical data obtained for 3 and 4 are compared with those reported previously for related cis-{Ru^(II)(NH_3)_4}^(2+) species [Coe, B. J. et al. J. Am. Chem. Soc. 2005, 127, 4845]. TD-DFT calculations on the complexes in 1–4 confirm that their lowest energy absorption bands are primarily Ru^(II) → L^A MLCT in character, while Ru^(II) → Tpm MLCT transitions are predicted at higher energies. DFT agrees with the Stark, but not the HRS measurements, in showing that β_0 increases with the electron-accepting strength of L^A. The 2D nature of the chromophores is evidenced by dominant β_(xxy) tensor components
Automatic deployment space exploration using refinement transformations
To manage the complex engineering information for real-time systems, the system under development may be modelled in a high-level architecture description language. This high-level information provides a basis for deployment space exploration as it can be used to generate a low-level implementation. During this deployment mapping many platform-dependent choices have to be made whose consequences cannot be easily predicted. In this paper we present an approach to the automatic exploration of the deployment space based on platform-based design. All possible solutions of a deployment step are generated using a refinement transformation. Non-conforming deployment alternatives are pruned as early as possible using simulation or analytical methods. We validate the feasibility of our approach by deploying part of an automotive power window optimized for its real-time behaviour using an AUTOSAR-like representation. First results are promising and show that the optimal solution can indeed be found efficiently with our approach
Evolution of crystallographic phases in (Sr<SUB>1-x</SUB>Ca<SUB>x</SUB>)TiO<SUB>3</SUB> with composition (x)
Results of X-ray powder diffraction, neutron powder diffraction, electron microdiffraction, and convergent beam electron diffraction (CBED) studies are presented to show that the space group of (Sr1-xCax)TiO3 (SCT) in the composition range 0.35<x≤0.55 cannot be Cmcm. The correct space groups are Pbcm for 0.35<x≤0.40 and Pbnm for 0.40<x≤0.55. The analysis of powder XRD data reveals that the structure of SCT is noncubic for x≥0.06. It is shown that four different types of orthorhombic phases appear in the SCT system with increasing Ca2+ content
Workflow and treatment results for computer-aided design and 3D-printed conformer therapy of congenital anophthalmia and microphthalmia
BACKGROUND/AIMS: To evaluate treatment with custom, three-dimensional (3D) printed conformers for socket expansion in congenital microphthalmia and anophthalmia (MICA). METHODS: Retrospective analysis of prospective cohort from 2016 to 2020. All children received custom-made 3D-printed conformers increasing in size. We measured height, width, thickness, surface and volume of first and consecutive conformers, as well as horizontal palpebral fissure length (HPF) at start and follow-up visits. We analysed these parameters for severely (45%-75%) affected children, based on affected axial length on ultrasonography. RESULTS: We included 18 cases (9 severe, 9 moderate) with a total of 174 conformers (88 severe, 86 moderate) and a mean follow-up of 2.8 years (range 1.3-4.8). The mean relative HPF increased from 77% to 93% with 16/17 cases reaching >80%, and 12/17 cases >90% symmetry. Horizontal and vertical conformer dimensions increased up to 10 months of treatment, with a steeper slope for the severe group (10.5% vs 5.5% for height and 9.0% vs 6.1% for width gain per treatment month, for severe and moderate MICA, respectively). After 10 months of treatment conformer height and width increased only slightly. No serious complications were observed. CONCLUSION: 3D-design and printing of solid conformers results in highly acceptable horizontal eyelid symmetry in the treatment of congenital MICA. The mean increase in conformer height and width in the first 10 months should be about 170% for moderate and about 200% for severe MICA. The presented conformer size formulas can aid ophthalmologists and ocularists to plan conformer treatment