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For the large-scale implementation of amine-based post-combustion CO2 capture, the energy consumption associated with the absorbent regeneration remains the most critical challenge. Despite efforts to reduce regeneration duty, such as using new amine formulations and modifying process configurations, an advanced method of overcoming this technical barrier is still required. Here, we introduce a novel approach to decreasing the heat requirement of absorbent regeneration by introducing metal ions catalyst into aqueous amine solution. Our approach uses the dual ability of amine in aqueous solution to both react with CO2 and complex with transition metal ions to reduce the heat of CO2 desorption via metal–amine complexation. Based on benchmarking monoethanolamine (MEA) absorbent and copper (Cu) ions, we developed a model that describes the process chemistry of Cu(II)–MEA–CO2–H2O to understand the speciation profiles under various conditions, particularly for Cu–MEA complexes. We conducted the comprehensive experiments to investigate the influence of Cu(II) addition on the performance of MEA-based CO2 capture process, including the CO2 absorption/desorption capacity, CO2 absorption/desorption rate, CO2 absorption temperature increase and heat of CO2 desorption. The results showed that adding Cu(II) to MEA solution significantly improved the CO2 capture performance, i.e. it mitigated the temperature increase during CO2 absorption, enhanced the CO2 desorption rate, increased the solvent’s cyclic CO2 capacity due to deep CO2 stripping. More importantly, the heat of CO2 desorption was reduced by 13.2–24.0% depending on the copper ion concentration. Our results indicate that metal–amine complexes play an important role in advancing the amine-based CO2 capture process and have potential application to industrial practice.

The solvent-based carbon capture process is the most matured and economical route for decarbonizing the power sector. In this process, aqueous monoethanolamine (MEA) is commonly used as the solvent for CO2 scrubbing from power plant and industrial flue gases. Generally, aqueous MEA with 30 wt% (or less) concentration is considered the benchmark solvent. The CO2 solubility data in aqueous MEA solution, used for modelling of the vapour-liquid equilibria (VLE) of CO2 in MEA solutions, are widely published for 30 wt% (or less) concentration. Aqueous MEA with higher concentrations (from 40 to 100 wt%) is considered in solvent-based carbon capture designs with techniques involving process intensification (PI). PI techniques could improve the process economics and operability of solvent-based carbon capture. Developing PI for application in capture process requires CO2 solubility data for concentrated MEA solutions. These data are however limited in literature. The modelling of the vapour-liquid equilibria (VLE) of CO2 in MEA solutions for PI-based solvent capture techniques involving stronger MEA solution of about 80 wt% concentration requires solubility data at the concentration. In this study, the data for 80 wt% MEA is presented for 40,60, 100 and 120oC. The experimental technique and analytical procedure in this study were validated by comparing the measurements for 30 wt% MEA with data from the literature. The data from this study can be fitted to VLE models such as electrolyte NRTL, extended UNIQUAC etc. which is an important component of solvent-based capture model using MEA as the solvent. More accurate VLE models will improve the prediction accuracy of capture level, rich loading etc. using PI-based solvent-based capture model.

A pilot-scale high-rate dark fermentative hydrogen production plant has been established in the campus of Feng Chia University to develop biohydrogen production pilot-plant technology. This pilot-plant system is composed of two feedstock storage tanks (0.75 m3 each), a nutrient storage tank (0.75 m3), a mixing tank (0.6 m3), an agitated granular sludge bed fermentor (working volume 0.4 m3), a gas–liquid–solid separator (0.4 m3) and a control panel. The seed mixed microflora was obtained from a lab-scale agitated granular sludge bed bioreactor. This pilot-scale fermentor was operated for 67 days at 35 °C, an organic loading rate (OLR) of 40–240 kg COD/m3/d, and the influent sucrose concentration of 20 and 40 kg COD/m3. Both biogas and hydrogen production rates increased with increasing OLR. However, the biomass concentration (volatile suspended solids, VSS) only increased with an increasing OLR at an OLR range of 40–120 kg COD/m3/d, whereas it decreased when OLR was too high (i.e., 240 kg COD/m3/d). The biogas consisted mainly of H2 and CO2 with a H2 content range of 23.2–37.8%. At an OLR of 240 kg COD/m3/d, the hydrogen content in biogas reached its maximum value of 37% with a hydrogen production rate (HPR) of 15.59 m3/m3/d and a hydrogen yield of 1.04 mol H2/mol sucrose. This HPR value is much higher than 5.26 m3/m3/d (fermented molasses substrate) and 1.56 m3/m3/d (glucose substrate) reported by other pilot-scale systems. Moreover, HPR was also greatly affected by pH. At an optimal pH of 5.5, the bacterial community became simple, while the efficient hydrogen producer Clostridium pasteurianum was dominant. The factors of energy output compared with the energy input (Ef) ranged from 13.65 to 28.68 on biohydrogen, which is higher than the Ef value on corn ethanol, biodiesel and sugarcane ethanol but in the similar range of cellulosic ethanol.

The interactions of Clostridium sp. and other non-hydrogen producing bacteria directly influence anaerobic hydrogen production. In this study, bacteria in a sucrose-feeding hydrogen-producing bioreactor were investigated via 16S rDNA-based analysis. Results showed that Clostridium pasteurianum, Klebsiella sp., and Streptococcus sp. were the predominant microorganisms. The Streptococcus sp. cells were found to localize inside hydrogen-producing granular sludge and were surrounded by clostridia. Significant oxygen consumption was found in the Klebsiella sp. pure culture experiment, in which oxidation reduction potential (ORP) dropped from 100 to −500 mV during the log phase within 2 h. Oxygen consumption by Streptococcus sp. was not significant, and it accumulated EPS under anaerobic conditions. Results suggest that Klebsiella sp. first utilized the oxygen to form anaerobic conditions in this system. Streptococcus sp., on the other hand, produced EPS complexes to strengthen the sludge granule followed by the mass growth of Clostridium sp.

Phase holdups play an important role in high-rate hydrogen production in an anaerobic fermentative reactor, especially in understanding biomass content, biogas flow and distribution that significantly affect the flow regimes change in the reactor. In the present study three-phase hydrogen producing reactor with different configurations were tested to investigate the phase holdups phenomenon and microbial community. It was found that the major fatty acids produced from the reactors were acetate and butyrate (HBu), accounting for 74.4–93.5% of total soluble microbial products (SMP). When the HRT was shortened from 8 to 1 h, the HBu was the dominant acid product among the soluble metabolites and the ratio of Ethanol/SMP was lower than 15.1. Moreover, the gas holdup ( ɛ g ) and solid holdup ( ɛ s ) increased but liquid holdup ( ɛ l ) decreased when the HRT was shortened. When the HRT was down to 1 h an increase in gas and solid holdups were noted. The gas holdups ( ɛ g ) increased in the range of 0.30–0.34, and the solid holdups ( ɛ s ) increased in the range of 0.32–0.34, which mean that the values of liquid holdups in high-rate fermentative hydrogen bioreactors could be decreased in the range of 0.38–0.32. Moreover, the empirical correlations of this study were satisfactory to predict the phase holdups in a dark-fermentation biohydrogen system. PCR-DGGE analysis revealed that bioreactor hydrodynamics under different HRTs significantly affects the occurrence of Streptococcus sp. and Bacillus sp. which mainly promotes granulation and retains high yielding hydrogen producing Clostridium sp. through their exopolysaccharides production. SEM results showed three dominant bacterial species namely Clostridium pasteurianum , Streptococcus sp. and Propionibacterium sp. in the bioreactors.

A high-rate hydrogen production process able to produce H 2 at a maximum rate of 15 L/L/hwas successfully developed by the Feng Chia University (FCU) biohydrogen research team.This highly efficient hydrogen fermentation system includes a 400 L pilot-scale systemconstructed for determining scale-up operation parameters for commercializing the bioH 2 production technology. The pilot-scale system is composed of a feedstock tank, mixingsystem, fermentor, gas/liquid separator and automatic control system. The fermentor isfed with sucrose (20 g COD/L) and operated at 35 C. A batch strategy is used for systemstart-up. The fermentor was first operated in a batch mode for two days and then switchedto a continuous-feeding mode (HRT 12 h) for one month. During the continuous operation,pH notably affected H 2 production efficiency and bacterial community. For the first 14-dayoperation, the H 2 production rate increased from 0.017 to 0.256 L/L/h with a pH variationfrom 5.0 to 7.0. The DGGE results indicate the presence of two Clostridium species (namely,Clostridium butyricum and Clostridium pasteurianum) in the fermenter. Stable hydrogenproduction rate was obtained at pH 5.5–6.0 when C. pasteurianum became dominant in themixed culture.Crown Copyright a 2009 Published by Elsevier Ltd on behalf of Professor T. Nejat Veziroglu.All rights reserved.

The aim of this study was to establish the particular biohydrogen-production related microbial community structure in a starch-feeding dark fermentation agitated granular sludge bed (AGSB) reactor which was operated under pH 6.0 and 5.5 as well as under different hydraulic retention times (HRTs). The bacterial community diversity and percent of their cell count of the bioreactor were ascertained using denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH) individually. Based on the comparison of bacterial structure and hydrogen production efficiency under different HRT, no conclusion could be made on whether the diversity of Clostridium community could directly affect the reactor performance in these two pH systems. However, bacterial cell counts showed that the viable number of dominated Clostridium sp. changed along with the hydrogen production rate (HPR). It was believed that it could directly affect the hydrogen production efficiency. The highest HPR and hydrogen yield (HY) occurred when the reactor was operated at HRT 0.5 h, while the ratio of Clostridium sp. cell count and Bifidobacterium sp. cell count over the total Eubacteria cell count were around 40% and 40–60%, respectively. Therefore, we suggested that bacterial species which could degrade starch, such as Bifidobacterium sp. in this study, broke down starch into small molecules first and then these less complex compounds were utilized by the Clostridium species for hydrogen production.

Molecular method such as PCR-DGGE using well-accepted universal 16S rDNA PCR primer sets was often applied on the study of Clostridium bacterial community. However, unsatisfied results were often obtained due to the difficulty of distinguishing coexisting Clostridium and other anaerobic microorganisms. In this study, a specific PCR primer set (Chis150f–ClostIr), based on the available rRNA gene sequences from the database, targeting only the majority of Clusters I and II Clostridia was designed and tested on both the pure culture Clostridium and dark fermentation sludge. It was demonstrated that this new primer set could not only successfully distinguish the coexisted Clostridium species but also revealed the existence of some Clostridium species in the sludge which could not be detected by using the universal primer set. This method successfully provides a detailed view on the Clostridium community responsible for an effective hydrogen production in dark fermentation system.

CNG channels are cyclic nucleotide-gated Ca2+-permeable channels that are suggested to be involved in the activity-dependent alterations of synaptic strength that are thought to underlie information storage in the CNS. In this study, we isolated an endogenous RNA transcript antisense to CNGα1 mRNA. This transcript was capable of down-regulating the expression of sense CNGα1 in theXenopus oocyte expression system. RT-PCR, Northern blot, and in situ hybridization analyses showed that the transcript was coexpressed with CNGα1 mRNA in many regions of human brain, notably in those regions that were involved in long-term potentiation and long-term depression, such as hippocampal CA1 and CA3, dentate gyrus, and cerebellar Purkinje layer. Comparison of expression patterns between adult and fetal cerebral cortex revealed that there were concurrent developmental changes in the expression levels of anti-CNG1 and CNGα1. Treatment of human glioma cell T98 with thyroid hormone T3caused a significant increase in anti-CNG1 expression and a parallel decrease in sense CNGα1 expression. These data suggest that the suppression of CNGα1 expression by anti-CNG1 may play an important role in neuronal functions, especially in synaptic plasticity and cortical development. Endogenous antisense RNA-mediated regulation may represent a new mechanism through which the activity of ion channels can be regulated in the human CNS.

A CMOS low dropout regulator (LDO) with a new pole-zero pairs cancellation compensation scheme is presented. LDO using this proposed compensation technique provides stable output voltage with any load capacitor. The only constraint on the equivalent series resistance (ESR) of the load capacitor is that it should be less than the load resistance. It is especially suitable for system-on-chip integration applications and board size reduction.

A 3.1-inch flexible active matrix OTFT-OLED display had been demonstrated on the plastic substrate with process temperature below 200°C. To realize the flexible AMOLED, we replace ITO by Ag and develop surface control method to achieve high uniformity OTFT array and the lifetime of half Id is over 5000hrs.