... now 1.2 Types of Fuel Cells There are six types of fuel cells that are currently in commercial use, di¤erentiated according to the type of electrolyte: Proton Exchange Membrane Fuel Cell (PEMFC), ... Methanol Fuel Cell (DMFC), Alkaline Fuel Cell (AFC), 1.2 Types of Fuel Cells Phosphoric Acid Fuel Cell (PAFC), Molten Carbonate Fuel Cell (MCFC), Solid Oxide Fuel Cell (SOFC) The characteristics of fuel ... relates proton conductivity as a function of water content m (S/m) = (0:5193 0:326) exp 1268 303:15 T : (2.15) 22 Proton Exchange Membrane Fuel Cell 2.5 Cell performance Fuel cell performance...
Ngày tải lên: 30/09/2015, 06:29
... Suitable for all sizes of power stations, kW to multi-MW Table 1.1 Main types of fuel cells and their characteristics and applications 1.3 Proton Exchange Membrane Fuel Cells (PEMFCs) Proton Exchange ... (PEMFCs) Proton Exchange Membrane Fuel Cells are also known as polymer electrolyte membrane fuel cells or polymer electrolyte fuel cells (PEFCs) Unlike other types of fuel cells, a typical PEMFC ... sputter-deposited catalyst layers for high performance PEMFCs [30] The performance of their cells with sputtered Pt catalysts of 0.1 mg cm-2 at cathode was nearly equivalent to that of a 22 ...
Ngày tải lên: 11/09/2015, 10:02
Integrated platinum carbon nanotube based electrocatalyst for high efficiency proton exchange membrane fuel cells 2
... the membranes were cation-exchanged to H+ form by boiling them in a 0.5M H2SO4 solution for hour and finally they were rinsed in boiling DI water for hour After this purification process, the membranes ... cycling ADT test, the electrode was held at 0.6 V for 40 s and at 1.8 V for 20 s for a total of 100 oxidation cycles In situ CV curves were measured before ADT and after every 10 oxidation cycles ... growth temperature, catalytic materials, gas flow rates and so forth 40 Currently a number of forms of CVD techniques are in wide use for CNT growth differing in their activation and process conditions,...
Ngày tải lên: 11/09/2015, 10:03
Integrated platinum carbon nanotube based electrocatalyst for high efficiency proton exchange membrane fuel cells 3
... Co(NO3)2 for h During the CNT growth, the carbon paper was heated at 600 °C for at 350 sccm Ar and 1.5 sccm H2 flow to obtain Co−Ni nanoparticles Then the temperature was increased to 800 °C for for ... maintained at these conditions for 30 and then subjected to CNT growth under a C2H2 flow of 7.5 sccm at 700 °C for h This growth process was rather time-consuming for its long heating conditioning ... temperature of 800 °C, thermal pyrolysis of C2H4 would take place to form amorphous carbon before it dissolves into Fe catalysts to form CNTs, thus it can be observed in Fig 3.2 (c) that even fewer...
Ngày tải lên: 11/09/2015, 10:03
Integrated platinum carbon nanotube based electrocatalyst for high efficiency proton exchange membrane fuel cells 4
... interface between the anode catalyst layer and the membrane The pathway for proton diffusion is thus very short from the reaction site to the membrane [38] In addition, the hydrogen oxidation ... hydrated Nafion membrane [42] and 2.1 Hz for the characteristic frequency of the diffusion impedance, the corresponding diffusion length for water transport was calculated as 11.7 µm for all the ... should be noted that water transport in membrane is associated with proton transport process due to the characteristic mechanism for Nafion conducting protons [43] According to previous studies...
Ngày tải lên: 11/09/2015, 10:03
Integrated platinum carbon nanotube based electrocatalyst for high efficiency proton exchange membrane fuel cells 5
... 0.6 and 1.8 V for a total of 100 oxidation cycles For each cycle, the electrode was held at 0.6 V for 40 s and at 1.8 V for 20 s, corresponding to a total oxidation time of 100 for the ADT test ... DHE for h, instead of a dynamic potential cycling as in the CV cycling oxidation process In this ADT test, the CV characterization for electrode electrochemical surface area was performed before ... PEMFC conditions The longterm stability information of Pt/CNT-based electrocatalysts from a fuel cell under real operating conditions would be very useful for the full evaluation of these electrocatalysts...
Ngày tải lên: 11/09/2015, 10:03
Integrated platinum carbon nanotube based electrocatalyst for high efficiency proton exchange membrane fuel cells 6
... cm-1 This technique is thus more suitable for fabricating low Pt loading electrode with high Pt utilization for PEMFC applications 6.2 Recommendations for Future Research The in situ grown CNT ... various simulated PEMFC environments for PEMFC applications Jalan et al [4] investigated the Pt-alloys supported on carbon black also in phosphoric acid fuel cells and found that the enhancement ... provide an efficient solution to the synthesis of Pt/CNT catalysts with reliable catalytic performance for PEMFC applications The Pt/CNT catalyst prepared by the combined method has demonstrated...
Ngày tải lên: 11/09/2015, 10:03
Development a new equation of polarization curve for a proton exchange membrane fuel cell at different channel geometry
... Scrivano et al [2] presented the results of an experimental analysis performed on an Exchange miniaturized, 6W Proton Membrane Fuel Cell (PEMFC) system, integrated with on-site hydrogen production ... general for fuel cells other than those used in [5] Khazaee [6] investigated numerically the effect of using different obstacles on the performances, current density and gas concentration for different ... distribution on the performance of a polymer electrolyte membrane fuel cell stack Their stack model consists of the flow network solver for pressure and mass flow distributions for the reactant gas...
Ngày tải lên: 09/09/2015, 10:32
Mass transport enhancement in a proton exchange membrane fuel cell
... Introduction 1.1 Fuel Cell Overview 1.2 Fuel Cell Thermodynamics and Electrochemistry 1.2.1 Theoretical Limit 1.2.2 Fuel Cell Performance 1.3 Proton Exchange Membrane (PEM) Fuel Cell 1.3.1 Components ... published experimental data for both forced and free convection PEMFC For forced convection fuel cells, a flow structure which delivers the reactant transversely to the membrane electrode assembly ... distinct characteristics for the six types of fuel cells commonly available in the market today Table 1.1: Distinct characteristics for the six different types of fuel cell Fuel Cell Electrolyte...
Ngày tải lên: 14/09/2015, 08:36
the market for foreign exchange suggested answers and solutions to end-of-chapter questions and problems
... discount or at a premium in the forward market? Answer: The forward market involves contracting today for the future purchase or sale of foreign exchange The forward price may be the same as ... account network allows for the efficient functioning of the foreign exchange market As an example of how the network of correspondent bank accounts facilities international foreign exchange transactions, ... cross rates of two forward foreign currencies and three currencies (CHF, ZAR, USD), the exchange would be as follows: 30 day forward CHF are sold for USD Dollars are bought at the forward selling...
Ngày tải lên: 12/07/2014, 10:57
the market for foreign exchange
... Arbitrage Spot Foreign Exchange Market Microstructure 4-2 Chapter Outline Continued The Forward Market – – – – – Forward Rate Quotations Long and Short Forward Positions Forward Cross -Exchange Rates ... Private information is an important determinant of spot exchange rates 4-29 The Forward Market Forward Rate Quotations Long and Short Forward Positions Forward Cross Exchange Rates Forward ... 1-mos forward 1-mos forward 1.9700 1.9700 5076 5076 3-most forward 3-most forward 1.9663 1.9663 5086 5086 6-mos forward 6-mos forward 1.9593 1.9593 5104 5104 9986 1.0014 The indirect quote for...
Ngày tải lên: 12/07/2014, 10:57
Fabrication of membrane electrode assembly for polymer electrolyte membrane fuel cell
... types of fuel cells can be found in the Fuel cell handbook 7th ed [1] or Fuel cell system explained by Larminie & Dicks [3] 1.2 Challenges for the Further Development of Fuel Cells The first fuel ... Introduction Polymer Electrolyte Membrane Fuel Cell is also known as Polymer Electrolyte Fuel Cell (PEFC) or Solid Polymer Electrolyte Fuel Cell (SPEFC) or Proton Exchange Membrane Fuel Cell As indicated ... common fuel cell types are Polymer Electrolyte Membrane Fuel Cell (PEMFC), Alkaline Fuel Cell (AFC), Phosphoric Acid Fuel Cell (PAFC), Molten Carbonate Fuel Cell (MCFC), and Solid Oxide Fuel Cell...
Ngày tải lên: 06/10/2015, 20:42
Poly(2,6 dimethyl 1,4 phenylene oxide) based semi interpenetrating polymer network proton exchange membranes for direct methanol fuel cells
... the cross-linked membranes: (a) PPO-PA membrane, (b) PPO-DEA membrane, (c) PPO-MID membrane, (d) PPO-ID membrane, (e) base-treated PPO-PA membrane, (f) base-treated PPO-DEA membrane, (g) base-treated ... simple polymer blends, leading to forced miscibility and the formation of mechanically strong membranes SIPNs are therefore useful for improving the membrane performance in a wide range of applications ... 2.2.2 Membrane Electrode Assembly 12 2.2.3 Proton Exchange Membranes 15 iv 2.2.3.1 Transport of Protons and Methanol in PEM 17 2.2.3.2 Mitigating the Tradeoff between Proton...
Ngày tải lên: 09/09/2015, 10:14
Preparation and characterization of the PVDF-based composite membrane for direct methanol fuel cells
... ketone) proton exchange membranes for fuel cell application J Membr Sci, 2005, 255(1-2):149-155 [4] V.S Silva, A Mendes, L.M Madeira, et al Proton exchange membranes for direct methanol fuel cells: ... compartment (CB) with time for PVDF-SPS membranes and Nafion-117 membrane 3.8 Oxidative stability of the PVDF-SPS composite membrane Oxidative stability of proton exchange membranes is one of the ... candidates for new proton exchange membranes J Membr Sci, 2002; 197(1-2): 231-242 Scott K, Taama W M, Argyropoulos P Performance of the direct methanol fuel cell with radiation-grafted polymer membranes...
Ngày tải lên: 05/09/2013, 16:11
Proton electrolyte membranes with hybrid matrix structures for assembling fuel cells
... REVIEW 11 2.1 Fuel Cells 11 2.1.1 Introduction 11 2.1.2 Fuel Cell Theory 12 2.1.3 Classification of Fuel Cells 13 2.2 Proton Exchange Membrane Fuel Cells (PEMFC) 15 2.3 Proton Exchange Membranes ... drive for zero emission vehicles has led to great technological strides in the development of PEMFC (Basu, 2007) 2.2 Proton Exchange Membrane fuel cells (PEMFCs) The proton exchange membrane fuel ... 5’-bibenzimidazole) PCC proton conducting channels PDDA poly(diallydimethylammonium chloride) PEEK polyether(ether)ketone PEM proton exchange membrane PEMFC fuel cell includes proton exchange membrane fuel cell...
Ngày tải lên: 11/09/2015, 16:05
The Business Case for Fuel Cells: Why Top Companies are Purchasing Fuel Cells Today doc
... assessed the market opportunity for fuel cells for backup power for state and local emergency response agencies The report found that fuel cells offer lower lifecycle costs than batteries for applications ... http://www.unfi.com/HydrogenFuelCells_SAR.aspx http://www.unfi.com/HydrogenFuelCells_SAR.aspx 60 http://www.unfi.com/HydrogenFuelCells_SAR.aspx 61 http://www.unfi.com/HydrogenFuelCells_SAR.aspx 59 36 U.S Foodservice Fuel ... generators, fuel cell power systems can fit in more locations Identification and Characterization of Near-Term Direct Hydrogen Proton Exchange Membrane Fuel Cell Markets, a 2006 study by Battelle for...
Ngày tải lên: 29/03/2014, 19:20
fuel processing for fuel cells
... minimised for low temperature proton exchange membrane fuel cells, but other fuel cells may well utilize it as a fuel (see Section 2.3.2) The same applies for methane in certain fuel cells Therefore, ... Hydrocarbon Reforming 80 Catalysts for Natural Gas/Methane Reforming 81 Catalysts for Reforming of LPG 84 Catalysts for Pre-Reforming of Hydrocarbons 86 Catalysts for Gasoline Reforming 88 Catalysts for ... Common Fossil Fuels Basic Definitions, Calculations and Legislation The Various Types of Fuel Cells and the Requirements of the Fuel Processor 12 PEM Fuel Cells 12 High Temperature Fuel Cells 15 3.1...
Ngày tải lên: 01/04/2014, 11:39
Báo cáo y học: " Human herpesvirus 6 major immediate early promoter has strong activity in T cells and is useful for heterologous gene expression" ppsx
... replicates and produces progeny in T cells very well; we therefore speculated that the MIE promoter would have stronger promoter activity in T cells than in other cells Here we identified the region ... recombinant varicella-zoster virus-infected cells These results suggest that HHV-6 MIEp can be used for driving gene expression Methods Cells MRC-5 cells, human lung fibroblasts, were cultured ... (FBS) MeWo cells, a human melanoma cell line, and U373 cells, a human astrocytoma cell line, were cultured in Dulbecco’s modified Eagle’s medium supplemented with 8% FBS Molt-3 cells, SupT1 cells, ...
Ngày tải lên: 11/08/2014, 21:21
electrocatalytic and fuel processing studies for portable fuel cells
... NITROGEN-CONTAINING CARBON CATALYSTS FOR THE OXYGEN REDUCTION REACTION IN PROTON EXCHANGE MEMBRANE FUEL CELL CATHODES CHAPTER INTRODUCTION 1.1 Advantages of Fuel Cells Fuel cells are promising alternative ... CATALYSTS FOR THE OXYGEN REDUCTION REACTION IN PROTON EXCHANGE MEMBRANE FUEL CELL CATHODES CHAPTER – INTRODUCTION 1.1 Advantages of Fuel Cells 1.2 How a PEM Fuel Cell ... a fuel directly into electricity without combustion There are several types of fuel cells, with the name usually indicating the type of electrolyte the cell uses The Proton Exchange Membrane Fuel...
Ngày tải lên: 14/11/2014, 13:12