We show that an ambiguity in setting the primitives of the matching with contracts model by Hatfield and Milgrom (2005) has serious implications for the model. Of the two ways to clear the ambiguity, the first (and what we consider more “clean”) remedy renders several of the results of the paper invalid in the absence of an additional irrelevance of removed contracts condition implicitly assume...

Materials & Methods: A retrospective review of all girls that underwent CPRE from December 1998 through September 2016 from a single institution was performed. Operative age and weight, type of pelvic immobilization, use of pelvic osteotomies, imaging, clinical course, and need for additional surgical procedures were recorded. Patients were deemed in retention if their clinical course was consi...

Gasification converts biomass into syngas; however, severe cleaning processes are necessary due to the presence of tars, particulates and contaminants. The aim this work is propose a method system based on tar physical adsorption coupled with production pure H2 via chemical looping process. Three fixed-bed reactors double-layer bed (NiO/Al2O3 Fe-based particles) working in three different steps...

Hydrogen is a clean and efficient fuel, considered as a potential and more sustainable energy substitute for fossil fuels. Biological hydrogen production stands out as an eco friendly process carried out under mild operating conditions with renewable resources. In the current work laboratory scale production of hydrogen using phototrophic purple non-sulphur bacteria Rhodobacter sphaeroides, ana...

The structure of water layers above hydrogen-covered Pt(111) surfaces at room temperature has been studied by ab initio molecular dynamics simulations based on periodic density functional theory calculations. Fully hydrogen-covered Pt(111) with additionally either a hydrogen vacancy or another hydrogen adatom have been considered. The resulting structures have been analyzed in detail as a funct...

oil exploration and production zones are very frequently contaminated with petroleum hydrocarbons or its derivatives. the most important exploration and production zones are located in south-west and south of the country, in iran. masjed soleiman city is located on an oil field. the soil of this region has been affected by the petroleum composition. mach petroleum seepages and springs (asphalt,...

Glycolic acid is a useful and important α-hydroxy that has broad applications. Herein, the homogeneous ruthenium catalyzed reforming of aqueous ethylene glycol to generate glycolic as well pure hydrogen gas, without concomitant CO2 emission, reported. This approach provides clean sustainable direction hydrogen, based on inexpensive, readily available, renewable using 0.5 mol % catalyst. In-dept...

Abstract Global fuel consumption and harmful gaseous emissions diverted energy sources to alternative means. Solar water splitting amidst other solar conversion methods is the most clean efficient means of hydrogen production. 21 st century technologies have delved into adopting nanomaterials high efficiency treat environmental pollution produce through electrochemical, photocatalytic, or elect...

in many hydroelectric dams, when the inflows are greater than the demand for energy, a portion of the water that could be used to generate electricity is diverted to the spillway and literally wasted. this energy,designated as “spilled turbinable energy”, could be used advantageously to generate other products or an energy vector that could be stored for later use, since in these situations the...