5-Hy­droxy­indan-1-one

In the title compound (5HIN), C9H8O2, is perfectly planar as all atoms, except the H atoms of both CH2 groups, lie on a crystallographic mirror plane. In the crystal, mol­ecules are linked by strong inter­molecular O—H⋯O hydrogen bonds, forming an infinite chain along [100], generating a C(8) motif

2-(Dibromo­meth­yl)benzoic acid

In the crystal structure of the title compound, C8H6Br2O2, the carboxyl groups are involved in pairs of O—H⋯O hydrogen bonds, which link the mol­ecules into inversion dimers

(Z)-4-(2-Hy­droxy­benzyl­idene)-1-methyl-2-phenyl-1H-imidazol-5(4H)-one

In the title compound, C17H14N2O2, the asymmetric unit comprises two mol­ecules that are comformationally similar [the dihedral angles between the phenyl rings in each are 46.35 (2) and 48.04 (3)°], with the conformation stabilized by intra­molecular O—H⋯N hydrogen bonds, which generate S(7) rings. In the crystal, inversion-related mol­ecules are linked by pairs of weak C—H⋯O hydrogen bonds, forming dimers with an R 2 2(16) graph-set motif. Weak inter-ring π–π stacking is observed in the structure, the shortest centroid-to-centroid distance being 3.7480 (13) Å

(E)-4-[(4-Diethyl­amino-2-hy­droxy­benzyl­idene)amino]­benzonitrile

The title compound, C18H19N3O, displays an E conformation with respect to the C=N double bond. The dihedral angle between the mean planes of the two benzene rings is 24.49 (3)°. An intra­molecular O—H⋯N hydrogen bond generates an S(6) ring. In the crystal, mol­ecules are linked by nonclassical inter­molecular C—H⋯O hydrogen bonds to form an infinite one-dimensional chain along [010], generating a C(8) motif

1-Hy­droxy-11H-benzo[b]fluoren-11-one

The title compound, C17H10O2, is nearly planar, the maximum atomic deviation being 0.053 (2) Å. In the mol­ecule, an intra­molecular O—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, inversion-related mol­ecules are linked by pairs of weak C—H⋯O hydrogen bonds, forming dimers. π–π stacking is observed in the crystal structure, the closest centroid–centroid distance being 3.7846 (16) Å

A White-Light-Emitting Small Molecule: Synthesis, Crystal Structure, and Optical Properties

A white-light-emitting small molecule (1) was synthesized and characterized by single-crystal X-ray diffraction. Compound 1 undergoes an excited-state intramolecular proton transfer (ESIPT) reaction, resulting in a tautomer that is in equilibrium with the normal species and exhibiting a dual emission that covers almost all of the visible spectrum, and consequently generates white light. Furthermore, the geometric structures, the frontier molecular orbitals (MOs), and the potential energy curves for 1 in the ground and the first singlet excited state were fully rationalized by density functional theory (DFT) and time-dependent DFT calculations. The results show that the forward ESIPT and backward ESIPT may happen on the same timescale, enabling the excited-state equilibrium to be established

7-Hy­droxy­indan-1-one

In the title compound, C9H8O2, an intra­molecular O—H⋯O hydrogen bond generates an S(6) ring. The dihedral angle between the mean plane of the S(6) ring and the benzene ring is 1.89 (2)°. In the crystal, inversion-related mol­ecules are linked by pairs of O—H⋯O hydrogen bonds, forming a cyclic dimers with R 2 2(12) graph-set motif. Weak inter­molecular C—H⋯Ocarbon­yl and C—H⋯Ohy­droxy hydrogen bonds link the dimers into chains along [010], generating two C(6) motifs that overlap three C atoms, forming R 2 2(8) ring motifs

Flow Boiling Heat Transfer in Microchannels

Flow boiling heat transfer to water in microchannels is experimentally investigated. The dimensions of the microchannels considered are 275 x 636 and 406 x 1063 um2. The experiments are conducted at inlet water temperatures in the range of 67–95°C and mass fluxes of 221–1283 kg/m2 s. The maximum heat flux investigated in the tests is 129 W/cm2 and the maximum exit quality is 0.2. Convective boiling heat transfer coefficients are measured and compared to predictions from existing correlations for larger channels. While an existing correlation was found to provide satisfactory prediction of the heat transfer coefficient in subcooled boiling in microchannels, saturated boiling was not well predicted by the correlations for macrochannels. A new superposition model is developed to correlate the heat transfer data in the saturated boiling regime in microchannel flows. In this model, specific features of flow boiling in microchannels are incorporated while deriving analytical solutions for the convection enhancement factor and nucleate boiling suppression factor. Good agreement with the experimental measurements indicates that this model is suitable for use in analyzing boiling heat transfer in microchannel flows