[2,6-Dioxo-1,2,3,6-tetra­hydro­pyrim­idine-4-carboxyl­ato(2−)]bis(pyrazino[2,3-f][1,10]phenanthroline)cobalt(II) dihydrate

The title complex, [Co(C5H2N2O4)(C14H8N4)2]·2H2O, features a slightly distorted octa­hedral geometry for Co due to the sterical requirements of the orotic acid and pyrazino[2,3-f][1,10]phenanthroline ligands. Inter­molecular hydrogen bonding between the uncoordinated water mol­ecules and the ligand stablizes the structure of the complex

A TD-DFT Study on the Photo-Physicochemical Properties of Chrysophanol from Rheum

As a naturally occurring anthraquinone pigment, chrysophanol (MHAQ) has attracted considerable attention in recent years owing to its efficient photosensitivity under the solar spectrum. Considering the successful use of time-dependent density functional theory (TD-DFT) in investigating the photo-physicochemical behaviors of dyes and pigments, we performed a study by means of TD-DFT calculations, which provided us with various excited state properties of chrysophanol, including absorption spectrum, lowest triplet excited-state energy, vertical electron affinity and vertical ionization potential. On the basis of the calculated results, the photosensitive mechanisms of chrysophanol were discussed and some deeper insights were gained. First, we indicated that the experimentally observed chrysophanol’s photo-damage to DNA in oxygen-free media is more likely to arise from MHAQ•+ rather than from T1 state chrysophanol. Second, we revealed that it is the MHAQ•− that is responsible for the O2•− generation in solvents. Based on the photosensitive activities, chrysophanol may be potentially used as the photodynamic medicine for clinical therapy of the diseases occurring on the shallow surface and vascular capillary diseases

Diaqua(2,6-dioxo-1,2,3,6-tetrahydropyrimidin-3-ide-4-carboxylato-κ2N3,O4)(1,10-phenanthroline-κ2N,N′)manganese(II)

The title compound, [Mn(C5H2N2O4)(C12H8N2)(H2O)2], was synthesized by the reaction of manganese(II) acetate and orotic acid in the presence of 1,10-phenanthroline. The crystal structure exhibits intermolecular N—H...O and O—H...O hydrogen bonds . The Mn coordination environment consists of an N3O3 donor set in an octahedral geometry

Effect of heat treatment on microstructures and mechanical properties in a full lamellar PM TiAl alloy

The effect of heat treatment on the microstructures and tensile properties of a powder metallurgical (PM) TiAl based alloy has been investigated in this paper. The near gamma (NG) microstructure is transformed to a full lamellar (FL) microstructure with an average grain size of 100 μm by heat treatments. The lamellar spacing of FL structure decreases with the increase of cooling rate. For cooling rates of 5, 10 and 50 °C/min, the lamellar spacing is 1.9, 1.0 and 0.8 μm respectively. The room temperature tensile properties exhibit an increasing trend with decrease of lamellar spacing