The Cover Feature shows a simple commercial direct methanol fuel cell in small detector ring Positron Emission Tomography (PET) camera for imaging of the electrocatalytic processes. PET images present coverage degree and distribution 11C-labeled with its derivatives along perforated plate holes anode (front) cathode (back) sides. inhomogeneous radioactivity confirms performance degradation on c...

The Direct Methanol Fuel Cell (DMFC) has attracted much attention due to its potential applications as a power source for transportation and portable electronic devices. Based on the advantages of the scaling laws, miniaturization promises higher efficiency and performance of power generating devices and the MicroDMFC is therefore an emergent technology. In this work, a set of experiments with ...

despite the role of oral corticosteroids in management of sever asthma, use of these drugs needs careful awareness of its many side effects. there are controversies about the role of methotrexate in lowering the need for corticosteroides in these patients. in this study an attempt has been made to determine methotrexate effects in corticosteroid dependent asthma. six patients were entered in a ...

For automotive applications, it is necessary to maximize the fuel conversion efficiency of a PEM direct-methanol fuel cell (DMFC) over the broadest possible dynamic range of power. The research reported here critically examines the efficiency of the DMFC stack when operated over a broad power range. This research establishes a basis for a control strategy that simultaneously: optimizes DMFC fue...

A one dimensional (1-D), isothermal model for a direct methanol fuel cell (DMFC) is introduced and solved numerically by simple finite difference scheme. By using numerical calculation, the can be extended to more complicated situation which not analytically. The considers kinetics of multi-step oxidation reaction at anode. Diffusion crossover are taken into account reduced potential due then e...

background  & aim: case-crossover  studies are the case-control  version of crossover studies. in these studies, cases and controls are the same subjects. the term crossover is applied for designs that all subjects pass through both treatment (exposure) and placebo (non-exposure) phases. in fact they are  crossover  of  subjects  between  periods  of  exposure  and  non-exposure.  this  design ...

Two types of inorganic/organic hybrids comprising Brønsted acid-base ionic groups have been prepared and studied for proton exchange membranes (PEM) applications. The hybrid membranes have a highly cross-linked silicon-oxygen backbone and trifluoromethanesulfonimide (HTFSI) doped organic amine groups. The Si-O backbone provides the membranes thermal/chemical/mechanical properties and the HTFSI-...

A class of 2D covalent organic polymers (COPs) incorporating a metal (such as Fe, Co, Mn) with precisely controlled locations of nitrogen heteroatoms and holes were synthesized from various N-containing metal-organic complexes (for example, metal-porphyrin complexes) by a nickel-catalyzed Yamamoto reaction. Subsequent carbonization of the metal-incorporated COPs led to the formation of COP-deri...