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In this study, waste bamboo chopsticks (WBC) were upgraded as solid bio-fuel by torrefaction using a tubular furnace with nitrogen as carrier gas. In order to fulfill the quality specifications of coal and industrial wood pellets, the effects of temperature and time of torrefaction on proximate and ultimate compositions and its dry-basis heating value (H HD ) were studied and elucidated. The results showed that the mass yield of WBC is 69% at 563 K and 40 min, while H HD of WBC is increased from 19.31 to 23.04 MJ kg −1 with an energy densification factor of 1.19, which satisfy the specification of quality D of Taiwan Power Co. and I3 industrial quality of Initiative Wood Pellets Buyers. Further, the torrefied WBC (WBC T ) pellets become convenient to store, transport and processing and hard to be rotten because of the modification of surface hydrophobicity. The ash content of WBC T is only 2.19 wt.% in wet basis, which is beneficial in practical boiler. Further, the energies needed for drying, heating and torrefaction is 2.31 MJ for processing 1 kg WBC with CO 2 emission of 0.339 kg. Therefore, WBC T would be practical alternative as solid bio-fuel for cofiring with coal.

Considering coordination effects, this study prepared a photocatalyst with a highly visible light respondence using co-doped titania with non-metal (nitrogen and sulfur) and lanthanide metal ions (cerium). As well, the photoelectrochemical characteristics and photocatalytic effects were tested. The feasibility was investigated on the power of the photoelectrochemical solar cell and the photodegradation of volatile organic compounds (VOCs) from indoor air pollution, taking toluene as a model compound. In this study, the different intensities of a light-emitting diode (LED) and the different initial concentrations (10–50 ppmv) were examined, and the kinetic model was addressed. The maximum power (Pm) at white light emitting diode (WLED) was 35.5 and 174.68 times that of the solar cell without cerium doping and without Ce, N and S doping, respectively. The decomposition efficiency (ηD) was more than 99.9% below 30 ppmv at 5050 WLED with 10 Ce/TiNxSyO2−x−y (10 Ce/TNST). The photocatalytic decomposition was elucidated according to the Langmuir-Hinshelwood model. The reaction rate constant (k) and adsorption equilibrium constant (KL) of 10 Ce/TNST with 5050 WLED in the range of 10–50 ppmv were 0.2637 ppmv min−1 and 0.7008 ppmv−1, respectively. This study succeeded in predicting optimum photodegradation conditions from the PECSC test. The photocurrent and power from the co-doped photocatalysts are related to the photodegradation efficiency.

In other studies the Integrated Process Rate (IPR) method was widely used to analyze the impact of various physical and chemical processes and their relative significance on PM2.5 in pollution episodes for specific sites; however, sources of pollution and their effect in planning emission control strategies were not considered. Using results of a brute force source sensitivity (BFSS) method may complement IPR. This paper integrates CMAQ-IPR and BFSS to examine the causes of a PM2.5 episode on Jan 15, 2010 across two air quality monitoring stations in Taichung, Taiwan (Shalu, a rural station and Situn, an urban station). Two pollution deterioration events (time intervals) were observed and simulated. When only CMAQ-IPR was used for simulation, the results revealed most pollution (>60%) was from local sources at the Situn Station. The two deterioration intervals differed however, as interval 1 showed a contribution from local emissions (49%), vertical advection (41%) and aerosols processes (10%). Interval 2 at Shalu Station was categorized as a downwind monitoring station, where emission from the grid constituted only 37%, and the majority of pollutants travelling by horizontal advection (56%), and to some extent, aerosols process (6%). Simulation by integrating IPR and BFSS (including diesel vehicles, gasoline vehicles/motorcycles, construction/road dust, iron/steel industries, and power plants around Taiwan) rendered to the type of physical or chemical process in which pollutants went through and its impact on the concentration of PM2.5 in the air quality monitoring station, which helped planning of emission control measures. Simulation results indicated improvement of PM2.5 concentrations in Situn and Shalu would be limited (only 0.2–4.2% contribution to deteriorating PM2.5 levels at the stations) even the emissions of the power plants and iron/steel industries in whole Taiwan were under control. However, by controlling the emissions of diesel vehicles, gasoline vehicles/motorcycles, and construction/road dust in whole Taiwan, the improvent is much enhanced (49–79% contribution to deteriorating PM2.5 levels at the stations), but it cost a lot. Nonethless, the improvement was quite significant by controlling the local emissions (around the monitoring station) of diesel vehicles, gasoline vehicles/motorcycles, and construction/road dust for Situn Station as they accounted for 72–85% of these three sources contribution to deteriorating PM2.5 levels at the station. For Shalu Station, it required a wide area of controlling the emissions from diesel vehicles, gasoline vehicles/motorcycles, and construction/road dust because there was 22–53% of these three sources contribution to deteriorating PM2.5 levels at the station from horizontal or vertical advection.

This study investigates the feasibility of applications of the plasma surface modification of photocatalysts and the removal of toluene from indoor environments. N-doped TiO2 is prepared by precipitation methods and calcined using a muffle furnace (MF) and modified by radio frequency plasma (RF) at different temperatures with light sources from a visible light lamp (VLL), a white light-emitting diode (WLED) and an ultraviolet light-emitting diode (UVLED). The operation parameters and influential factors are addressed and prepared for characteristic analysis and photo-decomposition examination. Furthermore, related kinetic models are established and used to simulate the experimental data. The characteristic analysis results show that the RF plasma-calcination method enhanced the Brunauer Emmett Teller surface area of the modified photocatalysts effectively. For the elemental analysis, the mass percentages of N for the RF-modified photocatalyst are larger than those of MF by six times. The aerodynamic diameters of the RF-modifiedphotocatalyst are all smaller than those of MF. Photocatalytic decompositions of toluene are elucidated according to the Langmuir-Hinshelwood model. Decomposition efficiencies (eta) of toluene for RF-calcined methods are all higher than those of commercial TiO2 (P25). Reaction kinetics ofphoto-decomposition reactions using RF-calcined methods with WLED are proposed. A comparison of the simulation results with experimental data is also made and indicates good agreement. All the results provide useful information and design specifications. Thus, this study shows the feasibility and potential use of plasma modification via LED in photocatalysis.

BOTH botulinum toxin1,2 and β-bungarotoxin3,4, isolated from the venom of Bungarus multicinctus, have been shown to block neuromuscular (NM) transmission by inhibition of the release mechanisms of the neurotransmitter. The inhibitory effect by either toxin is observed in the rat diaphragm only after a latent period, while the binding of both to the tissue seems to, be almost complete during the latent period3–5. There seem to be two processes for the inhibitory effect, the binding of toxins to the tissue, and the subsequent changes leading to the irreversible inhibition of the release mechanism of neurotransmitter4. The time course of the paralysis is markedly accelerated by an increase of stimulus frequency and delayed by procedures or factors which depress the activity of release mechanism, such as deficiency of calcium, increase of magnesium or decreased rate of nerve stimulation4–6. By contrast with botulinum toxin (ref. 2 and our unpublished data), β-bungarotoxin shows an initial facilitatory effect4, causing increases of the frequency of the spontaneous miniature end-plate potential and the quantal content of end-plate potential. Questions then arise as to whether or not they bind at a same site and act by a similar mechanism. We therefore studied the interaction between the two toxins in order to investigate the mechanism of the neurotransmitter release inhibition.