Understanding the water dynamics during sub-zero operation of polymer electrolyte fuel cells can help to optimize materials and operating strategies achieve successful freeze starts. This study employs sub-second X-ray tomographic microscopy effect downstream flow conditions on distributions dynamic starts from −30 °C by varying feed gas humidity. An increase in humidity resulted a decrease ele...

The reaction of hydrogen peroxide and  pheny -9-acridinecarboxylate in the presence of rhodamin B as a fluorophore leads to the emission of either bright blue light  or bright red light, depending on the structure of fluorescer and reaction conditions. The light emitter responsible for the Chemi Luminescence (CL) reaction is acridone and that the blue light produced with out the fluorescers...

The title hydro-chloride salt, C(18)H(21)N(2)O(+)·Cl(-), is an imidazolidinone catalyst, which was derived from L-phenyl-alanine through cyclization with acetophenone. The imidazolidinone compound has a five-membered heterocyclic ring including two chiral centres. The imidazolidinone ring displays an envelope conformation, with the flap protonated N atom lying 0.497 (3) Å above the mean plane o...

The resistance of the cathode oxygen reduction reaction in polymer electrolyte fuel cells must be reduced for improving performance. Therefore, it is important to thoroughly understand relationship between heterogeneous structures and cell However, difficult obtain such an understanding using experimental approaches typical uniform porous simulations. In this study, numerical analysis was used ...

Polymer electrolyte membrane fuel cells (PEMFCs) directly convert the chemical energy of the reactants into electrical energy and usually consist of a proton exchange membrane (PEM) sandwiched between two catalyst layers (CLs), two porous gas diffusion layers (GDLs) often coated with a microporous layer (MPL) on the CL side, and two bipolar plates with embedded gas channels. Protons and electro...

The oxidative dehydrogenation of ethane (ODH) to produce ethylene offers advantages compared the industry standard steam cracking, but its industrial application is hindered by costly air separation units needed supply oxygen. A chemical-looping-based (CL-ODH) scheme presented, in which oxygen carriers gaseous situ, then reacts with presence a catalyst at comparatively low temperature (500 °C)....

Atomic layer deposition (ALD) is a powerful deposition technique for constructing uniform, conformal, and ultrathin films in microelectronics, photovoltaics, catalysis, energy storage, and conversion. The possible pathways for silicon dioxide (SiO2) ALD using silicon tetrachloride (SiCl4) and water (H2O) without a catalyst have been investigated by means of density functional theory calculation...

a simple, clean, and environmentally benign three-component process for the synthesis of 2-amino-4hchromenes using [mim]cl, as an efficient catalyst under solvent-free conditions are described. a wide range of aromatic aldehydes easily undergoes condensations with 1-naphthol and malononitrile under solvent-free conditions to afford the desired products of good purity in excellent yields. taking...

The combination of the readily available chiral bisphosphine ligand Difluorphos with [Ir(COD)Cl](2) in THF resulted in a highly efficient catalyst system for asymmetric hydrogenation of quinolines at quite low catalyst loadings (0.05-0.002 mol%), affording the corresponding products with high enantioselectivities (up to 96%), excellent catalytic activities (TOF up to 3510 h(-1)) and productivit...

Vertical single-walled and double-walled carbon nanotube (SWNT and DWNT) arrays have been grown using a catalyst embedded within the pore walls of a porous anodic alumina (PAA) template. The initial film structure consisted of a SiOx adhesion layer, a Ti layer, a bottom Al layer, a Fe layer, and a top Al layer deposited on a Si wafer. The Al and Fe layers were subsequently anodized to create a ...