We report synthesis, properties, and optoelectronic device characteristics of six new indolocarbazole-acceptor conjugated copolymers prepared by Suzuki coupling reaction. Two different linkages of indolocarbazole (28IC and 39IC) and four acceptors of 2,3-didodecylthieno [3,4-b]pyrazine (TP12), 2,3-bis(4-(2-ethylhexyloxy) phenyl)thieno [3,4-b]pyrazine (TPO), 2,1,3-benzothiadiazole (BT), and 2,3-bis(4-(2-ethylhexyloxy)phenyl)quinoxaline (QO) were used to explore the effects of acceptor structure, linkage, and side group on the electronic and optoelectronic properties. The optical band gap (eV) of the studied copolymers were in the following order: P28IC-TPO (1.58) < P39IC-TP12 (1.79) < P28IC-TP12 (1.84) < P28IC-BT (2.09) < P28IC-QO (2.31) < P39IC-QO (2.34). The hole mobility and on-off ratios of the studied copolymers were in the ranges 1.66 × 10 -5 to 4 × 10 -4 cm 2 /V • s and 40-46900, respectively. It basically depended on the degree of intromolecular charge transfer between indolocarbazole and acceptor as well as the HOMO level. The power conversion efficiency (PCE) of the indolocarbazole-acceptor polymer/PC 61 BM or PC 71 BM based photovoltaic cells were in the range 0.14-1.40% under the illumination of AM 1.5G (100 mW/cm 2 ). P28IC-QO showed the best PCE among the studied copolymers because of its suitable HOMO/LUMO energy level, high molecular weight, good hole mobility, efficient PL quenching, and large V oc .

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Eleven ionic species and fine and coarse particle mass concentrations of fine (PM2.5) and coarse (PM10-2.5) particulate matter were investigated in Kaohsiung, southern Taiwan. The PM2.5 and PM10-2.5 particulate concentrations were 49-64 and 34-37 microg x m(-3), respectively. Fifty-five to 64% of the particulate matter less than 10 microm in aerodynamic diameter (PM10) mass was attributed to the PM2.5. PM2.5 concentrations at Daliao (a rural and industrial complex area) were higher than at Tzuoying (an urban and industrial complex area). Ionic species contributed 45-53% and 42-45% of PM2.5 and PM10, respectively. Potassium ions (K+), sulfate (SO4(2-)), and ammonium (NH4+) were predominant in PM2.5, whereas sodium, calcium, and magnesium ions were foremost in PM10-2.5. Nitrate (NO3-) existed in both the PM2.5 and PM10-2.5. Chloride (Cl-), NO3-, and NH4+ concentrations were higher at night than during the day, and they were easily transferred into the gas phase by photochemical reactions and temperature-induced volatilization. The NH4+/SO4(2-) ratios were 2.6 and 2.5 at Daliao and Tzuoying, respectively, which indicated that both sampling sites were rich in NH4+. Therefore, ammonium nitrate would be present in the area.

A simple method to fabricate carbon nanoparticles (CNPs) by passing an electric current through a carbon filament (CF) in liquid alcohol is reported. A large amount of gas bubbles (containing CO, H 2 , CO 2 , methane, ethane, acetylene and ethene) have been generated in the reaction between carbon and ethanol alcohol at a high temperature of about 2600 K. Scanning and transmission electron microscopy (TEM) images confirm the presence of carbon onion-like particles with diameters of about 20-50 nm. TEM images show that the spherical, disordered carbon onion-like particles seem to be in the majority. The carbon nanotubes are not formed under these conditions, which indicates that the nanoparticles are produced by thermal pyrolysis of alcohol vapors in the gas bubbles. Importantly, this carbonaceous production suggests that the carbon source in this method is mainly alcohol.