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51.
Enhanced power production of microbial fuel cells by reducing the oxygen and nitrogen functional groups of carbon cloth anode
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Shaoan Cheng Weifeng Liu Dan Sun Haobin Huang 《Surface and interface analysis : SIA》2017,49(5):410-418
The physicochemical properties of anode material are important for the electron transfer of anode bacteria and electricity generation of microbial fuel cells (MFCs). In this work, carbon cloth anode was pretreated with isopropanol, hydrogen peroxide (H2O2) and sodium hypochlorite (NaOCl) in order to reduce the anode functional groups. The influence of functional groups on the electrochemical properties of carbon cloth anode and power generation of MFCs was investigated. The anode pretreatments removed the surface sizing layer of carbon cloth and substantially reduced the contents of C‐O and pyridinic/pyrrolic N groups on the anode. Electrochemical impedance spectroscopy and cyclic voltammetry analyses of the biofilm‐matured anodes revealed an enhanced electrochemical electron transfer property because of the anode pretreatments. As compared with the untreated control (612 ± 6 mW m?2), the maximum power density of an acetate‐fed single‐chamber MFC was increased by 26% (773 ± 5 mW m?2) with the isopropanol treated anode. Additional treatment with H2O2 and NaOCl further increased the maximum power output to 844 ± 5 mW m?2 and 831 ± 4 mWm?2. A nearly inverse liner relationship was observed between the contents of C‐O and pyridinic/pyrrolic N groups on anodes and the anodic exchange current density and the power output of MFCs, indicating an adverse effect of these functional groups on the electricity production of anodes. Results from this study will further our understanding on the microbial interaction with carbon‐based electrodes and provide an important guidance for the modification of anode materials for MFCs in future studies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
52.
《先进技术聚合物》2018,29(9):2467-2476
Poly (caprolactone) membranes with addition of different poly (ethylene glycol) concentrations were prepared for separation of water/isopropanol azeotropic mixture by pervaporation process. Different characterization tests including Fourier transform infrared, scanning electron microscopy, water contact angle, and thermogravimetric analysis were carried out on the prepared membranes. In addition, the effect of poly (ethylene glycol) PEG content on the swelling degree and the performance of the prepared membranes in pervaporation process were investigated. According to the obtained results, all the membranes were water selective and the blend membrane containing 3 wt% PEG exhibited the best pervaporation performance with a water flux of 0.517 kg/m2 hour and separation factor of 1642 at the ambient temperature. Hydrophilicity improvement of the blend membranes was confirmed by constant decrease in water contact angle of the membranes as PEG content increased in the casting solution. Scanning electron microscopy cross‐sectional images indicated that the blend membranes containing PEG had a closed cellular structure. Furthermore, mechanical and thermal properties of the membranes decreased by adding PEG. 相似文献
53.
Acetanilide palladacycle: an efficient catalyst for room‐temperature Suzuki–Miyaura cross‐coupling reaction
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Anindita Dewan Zenith Buragohain Manoj Mondal Gayatri Sarmah Geetika Borah Utpal Bora 《应用有机金属化学》2014,28(4):230-233
The catalytic activity of three acetanilide palladacycles derived from easily accessible and commercially available acetanilide derivatives, viz. N‐phenylacetamide ( L1 ), N‐(4‐chlorophenyl)acetamide ( L2 ) and N‐(4‐methylphenyl)acetamide ( L3 ) has been examined in Pd‐catalyzed Suzuki–Miyaura reaction of arylboronic acid with aryl bromides at room temperature. The complex 1L3 exhibited efficient activity in the Suzuki–Miyaura reaction (up to 99% isolated yield) under mild reaction conditions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
54.
Nu Xiao 《Journal of fluorine chemistry》2010,131(3):439-1695
Chromatographic conditions for the separation of fluorinated amino acids and oligopeptides from their non-fluorinated counterparts were explored. The separation of six pairs of analytes, including both aromatic and aliphatic fluorocarbons, was investigated at various temperatures using both hydrocarbon and fluorocarbon columns and eluents. Our results show that when hydrocarbon eluents are used, fluorocarbon column provides better separation of fluorinated amino acids or oligopeptides from their non-fluorinated counterparts; when fluorocarbon eluents are used, hydrocarbon column provides better separation of fluorinated amino acids or oligopeptides from their non-fluorinated counterparts. These chromatographic behaviors reflect the fluorophilicity possessed by fluorinated amino acids and oligopeptides. 相似文献
55.
Tatiana S. Glazneva Vera P. Shmachkova Ludmila G. Simonova Evgeny A. Paukshtis 《Reaction Kinetics and Catalysis Letters》2007,92(2):303-309
Acidic properties of fiberglass materials were investigated using the adsorption of NH3 and the rate of isopropanol dehydration. It is shown that the specific catalytic activity of such materials and amount of
the Br?nsted acid sites per their surface unit (100 ?2) exceed considerably those in zeolite HZSM-5. 相似文献
56.
Ricardo Gomez Jaime Sanchez Rebeca Silva Tessy Lopez 《Reaction Kinetics and Catalysis Letters》1996,59(2):247-251
SnOx/Al2O3 catalysts were prepared by the sol-gel method using as starting reactants aluminium-tri-s-butoxide and (i) tetrabutyltin, (ii) tin tetrachloride and (iii) tin tetra-t-amyloxide. The gel derived catalysts show acidities of 0.72, 1.08 and 1.05 mol NH3/m2 and BET areas of 91, 112 and 189 m2/g. The activity and selectivity pattern for isopropanol decomposition were found to depend strongly on the tin precursor used. 相似文献
57.
A series of solvents were examined for the ligand free Pd(II)-catalyzed Suzuki reaction of 4-bromotoluene with phenylboronic acid. It was found that the PdCl2/i-PrOH system could efficiently inhibit the homo-coupling of phenylboronic acid and give a cross-coupling product in high yields. The substrates with a wide variety of functional groups were tolerated in the system. A possible mechanism for this system was proposed. 相似文献
58.
Vapour pressure measurements are carried out at different temperatures; the activity coefficients are calculated and compared with those devived from IR and NMR data (parts I and II).
Zur Thermodynamik des Isopropanol/n-Hexan und Isopropanol/n-Heptan Systems, III. Gas-Flüssig-Gleichgewichte
Zusammenfassung Es wurden Dampfdruckmessungen bei verschiedenen Temperaturen ausgeführt. Die daraus bestimmten Aktivitätskoeffizienten wurden mit den aus IR- und NMR-Daten berechneten (siehe Mitt. I und II) verglichen.相似文献
59.
Mg-Zn-Al三金属类水滑石的合成及其复合氧化物的催化性能 总被引:4,自引:0,他引:4
水滑石([Mg_6Al_2(OH)_(16)[CO_3·4H_2O)是一种类似于水镁石结构的层状阴离子黏土,其骨架为阳离子,层间为阴离子。如改变骨架中的金属阳离子或在层间引入不同的阴离子,就可形成各种新组成的类水滑石。水滑石对有机分子反应具有较高的催化活性和选择性,且可以作为复合氧化物催化剂的前体,应用广泛。它作为碱催化剂,可用于醇醛缩合;作为氧化还原催化剂,用于水煤气转化、NO的还原、甲烷氧化反应等犤1,2犦。作为一种具有特殊结构的化合物,各种双金属组分的水滑石或类水滑石的合成、性质与应用已受到广泛的重视犤3… 相似文献
60.
金属化聚邻甲苯胺膜修电极的性能研究 总被引:1,自引:0,他引:1
在聚邻甲苯胺(POT)膜修饰电极上用电化学法沉积Pt微粒,由SEM与XRD表征其表面形态与晶面取向,同时研究异丙醇在金属化POT膜电极上的氧化行为。结果表明,Pt在POT膜上的沉积呈现晶面择优取向的现象,况且POT质子掺杂后,由于电化学活性增强,影响了沉积铂微粒的尺寸和粒径分布,异丙醇的电氧化可发生在POT的电化学活性区,当电位大于0.70V(SCE)时,POT不再呈氧化还原活性,异丙醇的电氧化主要在铂微粒上进行,聚合物不仅作为铂微粒的载体而且自身参加反应,这种微异相催化体系需用新的模型描述。 相似文献