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101.
The progress of high temperature processes is generally described in terms of variation of the degree of conversion () with time (t). The present paper outlines a procedure for making use of-t plots for comparative assessment of productivity and energy requirements for a test system with respect to a reference, on the basis of some simplifying assumptions. It is assumed that the throughput is inversely proportional to reaction time as in the case of batch reactors and plug flow reactors. It is also assumed that the energy requirement is a simple function of process temperature. The principles outlined is illustrated with reference to some laboratory data for reduction of iron oxide by coal.The authors wish to thank Prof. P. R. Rao, Director National Metallurgical Laboratory, Jamshedpur, India, for providing facilities for experimental work and for according permission to publish this work. 相似文献
102.
103.
直接甲醇燃料电池作为未来清洁的动力能源,由于具有下列优点:操作温度低(<100℃)、燃料易储存和运输、能量效率高、污染低和燃料启动快而受到人们广泛的关注。阳极电催化剂是直接甲醇燃料电池最重要的组成部分。本文综述了近三年来直接甲醇燃料电池阳极电催化剂最新的研究进展,主要对催化剂制备方法、新型碳载体材料、催化剂类型作了详细的评述,展望了未来甲醇电催化氧化催化剂的发展,指出了电催化剂面临的问题。 相似文献
104.
Nickel foam and five nickel foam-based composite electrodes were prepared for being used as anode materials for the electrooxidation
of methanol in KOH solution containing 0.1 and 1.0 M of methanol. The layered electrodes composed of nickel foam, platinum
nanoparticles, polyaniline (PANI) and/or porous carbon (C) prepared in various assemblies. As shown by SEM analysis, depending
on the preparation conditions, the electrodes of different morphologies were obtained. Using the cyclic voltammetry method,
the oxidation of methanol on nickel foam electrode was observed in the potential range 0.4 V ↔ 0.7 V, where the Ni(OH)2/NiOOH transformation occurred. The presence of Pt particles in electrode gave rise to the increase in electrocatalytic activity
in this potential range. For electrodes containing dispersed platinum catalyst (Ni/Pt, Ni/PANI/Pt and Ni/C/Pt), the oxidation
of methanol was noted also in the potential range −0.5 V ↔ 0.1 V. The electrocatalytic activities of the examined electrodes
toward methanol oxidation at low potentials were in order Ni/Pt > Ni/C/Pt > Ni/PANI/Pt, whereas at high potentials in order
Ni/PANI/Pt > Ni/Pt> Ni/C/Pt > Ni. Among the examined electrodes, the most resistant to cyclic poisoning appeared to be the
Ni/C/Pt electrode.
Presented at the 4Th Baltic Conference on Electrochemistry, Greifswald, March 13–16, 2005 相似文献
105.
Atsuhisa Mimoto Sojiro Kon Takuya Motomura Minoru Inaba 《Journal of fluorine chemistry》2005,126(7):1101-1110
The Ni-based alloys, such as Ni-Co, Ni-Mn, Ni-Ag, Ni-Cu, Ni-Al and Ni-Si, prepared by hot isostatic pressing (HIP) at 1000 °C under 2 × 108 Pa for 2 h were employed as the anodes for electrolytic production of NF3. The current efficiencies for NF3 formation were 42-38, 52-40, 52-47, 63-62, 50 and 41% for Ni-Co, Ni-Mn, Ni-Ag, Ni-Cu, Ni-Al and Ni-Si alloys, respectively. The current efficiencies only on Ni-Cu alloys with Cu concentrations lower than 10 mol% were almost the same as those on Ni sheet and HIPed Ni anodes, whereas those on the other alloys used in this study were smaller compared with those on both Ni anodes. On the other hand, the current losses caused by anodic dissolution of Ni-Co, Ni-Mn, Ni-Ag, Ni-Cu, Ni-Al and Ni-Si alloy electrodes were 7.95-4.42, 6.40-7.02, 5.60-6.30, 3.34-6.33, 5.10 and 0.18%, respectively. The anode consumptions of Ni-5 mol% Cu and Ni-5 mol% Si alloys were almost the same or smaller compared with those of Ni sheet and HIPed Ni electrodes, though those of other alloys used were large compared with those of both Ni anodes. Consequently, addition of Cu to the nickel matrix is available for a cheaper cost of anode with keeping a same current efficiency as that on the Ni anode and addition of Si to the nickel matrix is effective for decreasing anode consumption largely. A Ni sheet electrode containing a trace of impurities, such as Co, Mn, Ag and Al, is also favorable as the anode for electrolytic production of NF3. 相似文献
106.
Weiland P 《Applied biochemistry and biotechnology》2003,109(1-3):263-274
The production of biogas for reducing fossil CO2 emissions is one of the key strategic issues of the German government and has resulted in the development of new process
techniques and new technologies for the energetic use of biogas. Progress has been made in cultivating energy crops for biogas
production, in using new reactor systems for anaerobic digestion, and in applying more efficient technologies for combined
heat and power production. Recently, integration of fuel cells within the anaerobic digestion process was started, and new
technologies for biogas upgrading and conversion to hydrogen were tested. This article describes the trends in Germany for
achieving more efficient energy production. 相似文献
107.
M. Lundbäck 《Polymer Degradation and Stability》2006,91(5):1071-1078
Plaques of branched polyethylene stabilized with 0.1 wt.% 4,4′-thiobis(6-tert-butyl-3-methylphenol) [Santonox® R] were aged at different temperatures between 75 and 95 °C in anaerobic (nitrogen or water) and aerobic (air or water saturated with air) media. Antioxidant concentration profiles were obtained by oxidation induction time (OIT) measurements using differential scanning calorimetry. Results obtained by high performance liquid chromatography of extracts confirmed that the gradual decrease in OIT with increasing ageing time was due to migration of antioxidant to the surrounding medium. The antioxidant concentration profiles along the plaque thickness direction were flat in the plaques aged in the non-aqueous media indicating that the migration of antioxidant to the surrounding medium was controlled by the low evaporation rate at the material boundary. Crystals of antioxidant were detected by optical microscopy on the samples exposed to nitrogen. The similarity of the antioxidant concentration profiles obtained after ageing in nitrogen and in air suggested that the fraction of the antioxidant oxidized is negligible in comparison with the loss of antioxidant by migration to the surrounding media. The antioxidant concentration profiles along the plaque thickness direction obtained after ageing in water were less flat, suggesting faster dissolution in the water phase than evaporation in the case of non-aqueous ageing. The antioxidant diffusivity could be determined from the aqueous experiments and was in reasonable agreement with data reported by Moisan. For the samples exposed to water, the loss of antioxidant was faster from the samples exposed to water saturated with air. This difference is attributed to a faster degradation of the antioxidant in the oxygen-containing water phase increasing the mass transport from the polymer phase boundary to the water phase. 相似文献
108.
Deniz Sinirlioglu Ali Ekrem Muftuoglu Kurtulus Golcuk Ayhan Bozkurt 《Journal of polymer science. Part A, Polymer chemistry》2014,52(13):1885-1897
This work uses a simple “grafting through” approach in the preparation of anhydrous poly(vinylidene fluoride) (PVDF)‐g‐PVTri polymer electrolyte membranes (PEMs). Alkaline‐treated PVDF was used as a macromolecule in conjunction with vinyltriazole in the graft copolymerization. The obtained polymer was subsequently doped with triflic acid (TA) at different stoichiometric ratios with respect to triazole units and the anhydrous PEMs (PVDF‐g‐PVTri‐(TA)x) were prepared. All samples were characterized by FTIR and 1H NMR. The composition of PVDF‐g‐PVTri was determined by energy dispersive spectroscopy. Thermal properties of the membranes were examined by thermogravimetric analysis and differential scanning calorimetry. The surface roughness and morphology of the membranes were studied using atomic force microscopy, X‐ray diffraction, and scanning electron microscopy. PVDF‐g‐PVTri‐(TA)3 (C3‐TA3) with a degree of grafting of 47.22% showed a maximum proton conductivity of 0.09 S cm?1 at 150 °C and anhydrous conditions. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1885–1897 相似文献
109.
Back Cover: Porous Mn2O3: A Low‐Cost Electrocatalyst for Oxygen Reduction Reaction in Alkaline Media with Comparable Activity to Pt/C (Chem. Eur. J. 29/2016) 下载免费PDF全文
Wenhai Wang Jing Geng Long Kuai Min Li Prof. Dr. Baoyou Geng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10256-10256