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TiO2thin films were prepared on fused quartz by using the sol–gel dip coating method followed by annealing. The effects of annealing temperature on the phase transition, crystalline agglomeration, surface topography and optical properties of the TiO2films were studied. Activation energy of the phase transition from the anatase to rutile phase was estimated about 64 kJ mol-1. Crystallite size did not vary significantly with the annealing temperature, but higher temperature led to the aggregation of nanocrystallines into large particles with wide size distribution due to the surface nucleation (SN) mode gradually replaced the interface nucleation (IN) mode. Both the optical transmittance and band gap of the TiO2thin films decrease as the annealing temperature increase. The highest optical transmittance over the visible wavelength region was obtained by the film annealed at 800 K, which was composed entirely of anatase phase.

Star formation is arguably the most important physical process in the cosmos. It is a fundamental driver of galaxy evolution and the ultimate source of most of the energy emitted by galaxies in the local universe. A correct interpretation of star formation rate (SFR) measures is therefore essential to our understanding of galaxy formation and evolution. Unfortunately, however, no single SFR estimator is universally available or even applicable in all circumstances: the numerous galaxies found in deep surveys are often too faint (or too distant) to yield significant detections with most standard SFR measures, and until now there have been no global multiband observations of nearby galaxies that span all the conditions under which star formation is taking place. To address this need in a systematic way, we have undertaken a multiband survey of all types of star-forming galaxies in the local universe. This project, the Star Formation Reference Survey (SFRS), is based on a statistically valid sample of 369 nearby galaxies that span all existing combinations of dust temperature, SFR, and specific SFR. Furthermore, because the SFRS is blind with respect to AGN fraction and environment, it serves as a means to assess the influence of these factors on SFR. Our panchromatic global flux measurements (including GALEXFUV + NUV, SDSS ugriz, 2MASS JHKs, Spitzer3-8 ?m, and others) furnish uniform SFR measures and the context in which their reliability can be assessed. This article describes the SFRS survey strategy, defines the sample, and presents the multiband photometry collected to date.

This study analyses the effects of dopamine receptor agonists and antagonists on rat gastrointestinal transit (GIT) in an attempt to identify the mechanisms involved. Dopamine (DA), apomorphine, quinpirole, bromocriptine and fenoldopam were given by subcutaneous (s.c.), intrathecal (i.t.), intracisternal (i.c.) and/or intraperitoneal (i.p.) routes. In general, DA (200 µg, i.t.), apomorphine (3, 5 and 10mg/kg, s.c.; or 10, 30 and 100 µg, i.t.), and bromocriptine (1, 5 and 10 mg/kg, s.c.) elicited decreases in gastrointestinal transit which were significantly antagonized by the D₂ receptor antagonists domperidone or alizapride (both 5 mg/kg, s.c.), but remained unaffected by the D₁ receptor antagonist SCH 23390 (5 mg/kg, s.c.). Similarly, DA (50, 100 and 200 µg, i.c.) and apomorphine (12 and 50 µg; i.c.) produced dose-dependent decreases in gastrointestinal transit amenable to blockade by the classical DA receptor antagonist haloperidol (10 µg, i.c.). The responses to apomorphine (3, 5 and 10 mg/kg, s.c.) were unaltered by 6-hydroxydopamine (100 mg/kg, i.p.)-induced sympathectomy but were antagonized by both propranolol (1 mg/kg, s.c.) and phentolamine (5 mg/kg, s.c.). Significantly, after bilateral (cervical) vagotomy, gastrointestinal transit was markedly reduced, but apomorphine (5 mg/kg, s.c.) apparently further reduced gastrointestinal transit. The D₁ agonists fenoldopam (5, 10 and 20 mg/kg, s.c.) significantly reduced GIT. Fenoldopam-induced antitransit effects were markedly modified by the D₁ receptor antagonist, SCH 23390 (5 mg/kg, s.c.); only the response induced by 5 mg/kg of fenoldopam was apparently antagonized by SCH 23390. The mixed D₂ and D₃ receptor agonist quinpirole (4 and 8 mg/kg, s.c.; or 8 mg/kg, i.p.; 200 µg, i.t.) did mimic DA eliciting significant reductions in gastrointestinal transit which, however, were not antagonized by domperidone (5 mg/kg, s.c.). Taken together, the present results support the contention that the decrease in rat gastrointestinal transit induced by DA and apomorphine may be mediated by an interaction with central and/or peripheral D₂ receptors. The presence of dopamine receptors (D₂) in the alimentary canal are strengthened by antitransit effect of fenoldopam and bromocriptine in the gastrointestinal tract. Copyright 1993, 1999 Academic Press

Organic solar cells (OSCs) have made enormous progress in recent years. However, OSCs still suffer from the low price–quality ratio since the complex synthesis of photovoltaic materials and the poor stability of the devices. Comparing with traditional large conjugated ladder-type non-fullerene acceptors, the unfused-ring acceptors with non-covalent intramolecular interactions could notably simplify the synthetic routes while maintaining the device performance. Here, we designed and synthesized two A1-D-A2-D-A1–type non-fullerene acceptors named BDTC-F and BDTC-Cl based on 1,3-bis(4-(2-ethylhexyl)-thiophen-2-yl)-5,7-bis(2-ethylhexyl)-benzo[1,2-c:4,5c']dithiophene-4,8-dione (BDD) as A2unit. With cyclopenta[2,1-b:3,4-b']dithiophene functions as the D unit, the weak O⋯S interaction between A2and D units is formed, which reduces the torsion angle between them and increases the planarity of the molecular backbone. Furthermore, the participation of BDD could deepen the energy levels of these two acceptors, makes it possible to decrease the energy loss of the corresponding devices. When blending with polymer donor PM6, devices based on both acceptors exhibit PCEs over 10% with low energy losses of 0.59 and 0.57 eV for BDTC-F and BDTC-Cl, respectively. Moreover, the devices based on PM6:BDTC-F and PM6:BDTC-Cl demonstrate excellent air stability. After stored in the ambient atmosphere without encapsulation for 1,200 h, devices based on these two acceptors retained over 96% of their initial PCEs. These results demonstrate that designing the A1-D-A2-D-A1–type acceptor with non-covalent intramolecular interactions is an effective strategy to construct low-cost and air-stable OSCs.