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971.
972.
Partial oxidation of simulated hot coke oven gas to syngas over Ru-Ni/Mg(Al)O catalyst in a ceramic membrane reactor 下载免费PDF全文
Hydrogen amplification from simulated hot coke oven gas (HCOG) was investigated in a BaCo0.7Fe0.2Nb0.1O3−δ (BCFNO) membrane reactor
combined with a Ru-Ni/Mg(Al)O catalyst by the partial oxidation of hydrocarbon compounds under atmospheric pressure. Under optimized
reaction conditions, the dense oxygen permeable membrane had an oxygen permeation flux around 13.3 ml/(cm2·min). By reforming of the
toluene and methane, the amount of H2 in the reaction effluent gas was about 2 times more than that of original H2 in simulated HCOG. The
Ru-Ni/Mg(Al)O catalyst used in the membrane reactor possessed good catalytic activity and resistance to coking. After the activity test, a small
amount of whisker carbon was observed on the used catalyst, and most of them could be removed in the hydrogen-rich atmosphere, implying
that the carbon deposition formed on the catalyst might be a reversible process. 相似文献
973.
Zohreh Khani Gilles Taillades Deborah J. Jones Jacques Rozière 《Journal of solid state chemistry》2009,182(4):790-208
Low temperature routes have been developed for the preparation of BaCe0.9Y0.1O2.95 (BCY10) and BaZr0.9Y0.1O2.95 (BZY10) in the form of nanoparticulate powders for use after densification as ceramic membranes for a proton ceramic fuel cell. These methods make use on the one hand of the chelation of metal (II), (III) and (IV) ions by acrylates (hydrogelation route) and on the other of the destabilisation and precipitation of micro-emulsions. Both routes lead to single phase yttrium doped barium cerate or zirconate perovskites, as observed by X-ray diffraction, after thermal treatment at 900 °C for 4 h for BCY10 and 800 °C for BZY10. These temperatures, lower than those usually used for preparation of barium cerate or zirconate, lead to oxide nanoparticles of size <40 nm. Dense ceramics (?95%) are obtained by sintering BCY10 pellets at 1350 °C and BZY10 pellets at 1500 °C for 10 h. The water uptake of compacted samples at 500 °C is 0.14 wt% for BCY10 and 0.26 wt% for BZY10. Total conductivities in the range 300-600 °C were determined using impedance spectroscopy in a humidified nitrogen atmosphere. The total conductivity was 1.8×10−2 S/cm for BCY10 and 2×10−3 S/cm for BZY10 at 600 °C. The smallest perovskite nanoparticles and highest conductivities were obtained by hydrogelation of precursor barium, zirconium, cerium and yttrium acrylates. 相似文献
974.
Yong Tao Jing-Fu Liu Xia-Lin Hu Hong-Cheng Li Thanh Wang Gui-Bin Jiang 《Journal of chromatography. A》2009,1216(35):6259-6266
By using ionic liquid as membrane liquid and tri-n-octylphosphine oxide (TOPO) as additive, hollow fiber supported liquid phase microextraction (HF-LPME) was developed for the determination of five sulfonamides in environmental water samples by high-performance liquid chromatography with ultraviolet detection The extraction solvent and the parameters affecting the extraction enrichment factor such as the type and amount of carrier, pH and volume ratio of donor phase and acceptor phase, extraction time, salt-out effect and matrix effect were optimized. Under the optimal extraction conditions (organic liquid membrane phase: [C8MIM][PF6] with 14% TOPO (w/v); donor phase: 4 mL, pH 4.5 KH2PO4 with 2 M Na2SO4; acceptor phase: 25 μL, pH 13 NaOH; extraction time: 8 h), low detection limits (0.1–0.4 μg/L, RSD ≤ 5%) and good linear range (1–2000 ng/mL, R2 ≥ 0.999) were obtained for all the analytes. The presence of humic acid (0–25 mg/L dissolved organic carbon) and bovine serum albumin (0–100 μg/mL) had no significant effect on the extraction efficiency. Good spike recoveries over the range of 82.2–103.2% were obtained when applying the proposed method on five real environmental water samples. These results indicated that this present method was very sensitive and reliable with good repeatabilities and excellent clean-up in water samples. The proposed method confirmed hollow fiber supported ionic liquid membrane based LPME to be robust to monitoring trace levels of sulfadiazine, sulfamerazine, sulfamethazine, sulfadimethoxine and sulfamethoxazole in aqueous samples. 相似文献
975.
Cotton fabric was coated with chitosan (CS) and polyethylene glycol (PEG) followed by freeze‐drying. The influence of PEG on the physical characteristics and the surface morphology was investigated. The scanning electron microscopy of the coated fabric revealed a porous structure. The porosity of the material was 54–70% and the pore size was in the range of 75–120µm. The increase in the PEG content in the blend composition led to an enhanced destabilization of pores, leading to an increase in the pore size with elongated morphology. There seems to be phase separation between the two components which is an important factor for the observed behavior of the porous structure. The Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) showed that the CS and PEG have limited interaction. DSC suggested that addition of PEG to CS does not interfere with the crystallization behavior due to limited interaction with CS. The thermogravimetric analysis (TGA) showed that the membranes are thermally stable and PEG enhances the thermal stability of the CS coated membranes. The air and water permeability of the membranes tended to decrease with the increase in the PEG content. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
976.
Takeshi Kondo Sangchul Lee Kensuke Honda Takeshi Kawai 《Electrochemistry communications》2009,11(8):1688-1691
Boron-doped diamond hollow fiber membrane (BDD–HFM) was fabricated as a novel type of porous conductive diamond. BDD–HFM was obtained by deposition of BDD polycrystalline film onto a quartz filter substrate consisting of quartz fibers, followed by etching of the substrate in HF/HNO3 aqueous solution. Cross-sectional scanning electron microscope (SEM) observation showed the inner diameter and wall thickness of the BDD hollow fibers were in the range of 0.4–2 and 0.2–2 μm, respectively. The BDD–HFM electrode exhibited a relatively large double-layer capacitance (ca. 13 F g−1) in 0.1 M H2SO4. Electrochemical AC impedance properties were simulated using an equivalent circuit model containing a transmission line model, which indicated characteristics of a porous electrode material. 相似文献
977.
Hana Robson Marsden Nina A. Elbers Paul H. H. Bomans Dr. Nico A. J. M. Sommerdijk Dr. Alexander Kros Dr. 《Angewandte Chemie (International ed. in English)》2009,48(13):2330-2333
Let's get together : A minimal model system was developed to mimic the SNARE‐protein‐mediated fusion of biological membranes (see picture). Fusion between two populations of liposomes is controlled by a pair of complementary lipidated oligopeptides that form noncovalent coiled‐coil complexes and thereby force the membranes into close proximity to promote fusion. The model system displays the key characteristics of in vivo fusion events.
978.
The effect of perfluorooctanesulphonic acid (PFOS) on lipid membranes was studied using supported 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayer as the model membrane. Phospholipid bilayer was deposited on gold electrode using a combination of the Langmuir–Blodgett and Langmuir–Schaefer (LB/LS) techniques. Electrodes were modified with two different types of membranes: DMPC bilayers initially containing PFOS and pure DMPC bilayers later exposed to the PFOS solutions. Such approach allowed studying both the changes in membrane characteristic imposed by the perfluorinated compound present in the model membrane and the process of its incorporation into the membrane. Studies with anticancer drug doxorubicin revealed that PFOS inhibits drug transport through the phospholipid bilayer and its effect can be compared to that of cholesterol. Moreover, the different trends observed in the changes in electron transfer rate constant (ks) calculated for ferricyanides and in peak current of hexaamineruthenium chloride showed that electrostatic interactions between electroactive probes and PFOS molecules incorporating into phospholipid bilayers play an important role and should be taken into account while explaining the interactions of perfluorooctanesulphonic acid with model biological membranes. 相似文献
979.
Heqing Jiang Haihui Wang Prof. Dr. Fangyi Liang Steffen Werth Dr. Thomas Schiestel Dr. Jürgen Caro Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(16):2807-2807
Hollow fiber membranes from mixed‐conducting perovskites can separate oxygen selectively from gas mixtures. Wall thicknesses as low as 150 μm can be obtained by a wet spinning process, and oxygen fluxes are thereby obtained that are relevant for technical applications. In their Communication on page 2983 ff., H. Wang, J. Caro and co‐workers describe the complete decomposition of nitrous oxide with such membranes. This method offers new opportunities to reduce emissions of this greenhouse gas.
980.
Olga Nemulenzi Byron Mhaka Ewa Cukrowska Olof Ramström Hlanganani Tutu Luke Chimuka 《Journal of separation science》2009,32(11):1941-1948
The potential of combination of liquid membranes (microporous membrane liquid–liquid extraction) and molecularly imprinted polymers (MIPs) was performed using 17β‐estradiol (E2) as model compound. The model compound was extracted from aqueous sample through a hydrophobic porous membrane that was impregnated with hexane/ethyl acetate (3:2), which also formed part of the acceptor phase. In the acceptor phase, the compound was bound onto MIP particles that were also part of the organic phase. The potential of such combination was optimised for the type and amount of MIP particles in the organic acceptor phase, the extraction time, and the type of organic acceptor solvent. Ultrasound assisted binding of E2 onto MIP particles was also investigated. MIPs prepared by precipitation polymerization were found to be superior to those prepared by bulk polymerization. Increase in the extraction time and the amount of MIP particles in the acceptor phase led to more E2 binding onto the MIP particles. Hexane/ethyl acetate (3:2) as an organic acceptor was found to give higher E2 binding onto MIP particles compared to toluene, diethyl ether, and hexane. Ultrasound was furthermore found to increase the binding of E2 onto MIP particles. The selectivity of the technique was demonstrated by extracting wastewater and where clean chromatograms were obtained compared to liquid membrane extractions (SLMs) alone. 相似文献